Move patterns into a module

18 files changed, 366 insertions, 1495 deletions

diff --git a/src/ast.c b/src/ast.c
index 5f4e24f1..75795d61 100644
--- a/src/ast.c
+++ b/src/ast.c
@@ -165,6 +165,7 @@ CORD ast_to_xml(ast_t *ast)
     T(Use, "<Use>%r%r</Use>", optional_tagged("var", data.var), xml_escape(data.path))
     T(InlineCCode, "<InlineCode>%r</InlineCode>", xml_escape(data.code))
     T(Deserialize, "<Deserialize><type>%r</type>%r</Deserialize>", type_ast_to_xml(data.type), ast_to_xml(data.value))
+    T(Extend, "<Extend name=\"%s\">%r</Extend>", data.name, ast_to_xml(data.body))
     default: return "???";
 #undef T
     }
diff --git a/src/ast.h b/src/ast.h
index b5b1ad3c..cad7bb64 100644
--- a/src/ast.h
+++ b/src/ast.h
@@ -143,6 +143,7 @@ typedef enum {
     Use,
     InlineCCode,
     Deserialize,
+    Extend,
 } ast_e;
 
 struct ast_s {
@@ -331,6 +332,10 @@ struct ast_s {
             ast_t *value;
             type_ast_t *type;
         } Deserialize;
+        struct {
+            const char *name;
+            ast_t *body;
+        } Extend;
     } __data;
 };
 
diff --git a/src/compile.c b/src/compile.c
index f228148a..2cc20f39 100644
--- a/src/compile.c
+++ b/src/compile.c
@@ -15,7 +15,6 @@
 #include "stdlib/integers.h"
 #include "stdlib/nums.h"
 #include "stdlib/paths.h"
-#include "stdlib/patterns.h"
 #include "stdlib/text.h"
 #include "stdlib/util.h"
 #include "structs.h"
@@ -39,7 +38,7 @@ static CORD compile_string_literal(CORD literal);
 
 CORD promote_to_optional(type_t *t, CORD code)
 {
-    if (t == PATH_TYPE || t == PATH_TYPE_TYPE || t == MATCH_TYPE) {
+    if (t == PATH_TYPE || t == PATH_TYPE_TYPE) {
         return code;
     } else if (t->tag == IntType) {
         switch (Match(t, IntType)->bits) {
@@ -442,7 +441,7 @@ static void add_closed_vars(Table_t *closed_vars, env_t *enclosing_scope, env_t
         add_closed_vars(closed_vars, enclosing_scope, env, Match(ast, Deserialize)->value);
         break;
     }
-    case Use: case FunctionDef: case ConvertDef: case StructDef: case EnumDef: case LangDef: {
+    case Use: case FunctionDef: case ConvertDef: case StructDef: case EnumDef: case LangDef: case Extend: {
         errx(1, "Definitions should not be reachable in a closure.");
     }
     default:
@@ -497,7 +496,6 @@ PUREFUNC CORD compile_unsigned_type(type_t *t)
 CORD compile_type(type_t *t)
 {
     if (t == RNG_TYPE) return "RNG_t";
-    else if (t == MATCH_TYPE) return "Match_t";
     else if (t == PATH_TYPE) return "Path_t";
     else if (t == PATH_TYPE_TYPE) return "PathType_t";
 
@@ -516,8 +514,6 @@ CORD compile_type(type_t *t)
         auto text = Match(t, TextType);
         if (!text->lang || streq(text->lang, "Text"))
             return "Text_t";
-        else if (streq(text->lang, "Pattern"))
-            return "Pattern_t";
         else
             return CORD_all(namespace_prefix(text->env, text->env->namespace->parent), text->lang, "$$type");
     }
@@ -558,8 +554,6 @@ CORD compile_type(type_t *t)
         case ArrayType: case TableType: case SetType:
             return CORD_all("Optional", compile_type(nonnull));
         case StructType: {
-            if (nonnull == MATCH_TYPE)
-                return "OptionalMatch_t";
             if (nonnull == PATH_TYPE)
                 return "OptionalPath_t";
             if (nonnull == PATH_TYPE_TYPE)
@@ -680,7 +674,7 @@ CORD optional_into_nonnone(type_t *t, CORD value)
     case IntType:
         return CORD_all(value, ".value");
     case StructType:
-        if (t == MATCH_TYPE || t == PATH_TYPE || t == PATH_TYPE_TYPE)
+        if (t == PATH_TYPE || t == PATH_TYPE_TYPE)
             return value;
         return CORD_all(value, ".value");
     default:
@@ -695,8 +689,6 @@ CORD check_none(type_t *t, CORD value)
     // complain about excessive parens around equality comparisons
     if (t->tag == PointerType || t->tag == FunctionType || t->tag == CStringType)
         return CORD_all("({", value, " == NULL;})");
-    else if (t == MATCH_TYPE)
-        return CORD_all("({(", value, ").index.small == 0;})");
     else if (t == PATH_TYPE)
         return CORD_all("({(", value, ").type.$tag == PATH_NONE;})");
     else if (t == PATH_TYPE_TYPE)
@@ -1168,7 +1160,7 @@ static CORD _compile_statement(env_t *env, ast_t *ast)
         default: code_err(ast, "Update assignments are not implemented for this operation");
         }
     }
-    case StructDef: case EnumDef: case LangDef: case FunctionDef: case ConvertDef: {
+    case StructDef: case EnumDef: case LangDef: case Extend: case FunctionDef: case ConvertDef: {
         return CORD_EMPTY;
     }
     case Skip: {
@@ -1730,8 +1722,13 @@ static CORD _compile_statement(env_t *env, ast_t *ast)
                 code_err(ast, "Could not find library");
 
             CORD initialization = CORD_EMPTY;
-            const char *lib_id = Text$as_c_string(
-                Text$replace(Text$from_str(use->path), Pattern("{1+ !alphanumeric}"), Text("_"), Pattern(""), false));
+
+            char *lib_id = String(use->path);
+            for (char *p = lib_id; *p; p++) {
+                if (!isalnum(*p) && *p != '_')
+                    *p = '_';
+            }
+
             for (size_t i = 0; i < tm_files.gl_pathc; i++) {
                 const char *filename = tm_files.gl_pathv[i];
                 initialization = CORD_all(
@@ -2165,7 +2162,6 @@ CORD compile_none(type_t *t)
 
     if (t == PATH_TYPE) return "NONE_PATH";
     else if (t == PATH_TYPE_TYPE) return "((OptionalPathType_t){})";
-    else if (t == MATCH_TYPE) return "NONE_MATCH";
 
     switch (t->tag) {
     case BigIntType: return "NONE_INT";
@@ -2597,8 +2593,6 @@ CORD compile(env_t *env, ast_t *ast)
         CORD lang_constructor;
         if (!lang || streq(lang, "Text"))
             lang_constructor = "Text";
-        else if (streq(lang, "Pattern"))
-            lang_constructor = lang;
         else
             lang_constructor = CORD_all(namespace_prefix(Match(text_t, TextType)->env, Match(text_t, TextType)->env->namespace->parent), lang);
 
@@ -3752,7 +3746,7 @@ CORD compile(env_t *env, ast_t *ast)
     case Defer: code_err(ast, "Compiling 'defer' as expression!");
     case Extern: code_err(ast, "Externs are not supported as expressions");
     case TableEntry: code_err(ast, "Table entries should not be compiled directly");
-    case Declare: case Assign: case UpdateAssign: case For: case While: case Repeat: case StructDef: case LangDef:
+    case Declare: case Assign: case UpdateAssign: case For: case While: case Repeat: case StructDef: case LangDef: case Extend:
     case EnumDef: case FunctionDef: case ConvertDef: case Skip: case Stop: case Pass: case Return: case DocTest: case PrintStatement:
         code_err(ast, "This is not a valid expression");
     default: case Unknown: code_err(ast, "Unknown AST");
@@ -3762,7 +3756,6 @@ CORD compile(env_t *env, ast_t *ast)
 CORD compile_type_info(type_t *t)
 {
     if (t == RNG_TYPE) return "&RNG$info";
-    else if (t == MATCH_TYPE) return "&Match$info";
     else if (t == PATH_TYPE) return "&Path$info";
     else if (t == PATH_TYPE_TYPE) return "&PathType$info";
 
@@ -3773,8 +3766,6 @@ CORD compile_type_info(type_t *t)
         auto text = Match(t, TextType);
         if (!text->lang || streq(text->lang, "Text"))
             return "&Text$info";
-        else if (streq(text->lang, "Pattern"))
-            return "&Pattern$info";
         return CORD_all("(&", namespace_prefix(text->env, text->env->namespace->parent), text->lang, "$$info)");
     }
     case StructType: {
@@ -4206,6 +4197,12 @@ CORD compile_top_level_code(env_t *env, ast_t *ast)
         env_t *ns_env = namespace_env(env, def->name);
         return CORD_all(code, def->namespace ? compile_top_level_code(ns_env, def->namespace) : CORD_EMPTY);
     }
+    case Extend: {
+        auto extend = Match(ast, Extend);
+        env_t *ns_env = namespace_env(env, extend->name);
+        ns_env->libname = env->libname;
+        return compile_top_level_code(ns_env, extend->body);
+    }
     case Extern: return CORD_EMPTY;
     case Block: {
         CORD code = CORD_EMPTY;
@@ -4258,6 +4255,9 @@ static void initialize_vars_and_statics(env_t *env, ast_t *ast)
         } else if (stmt->ast->tag == LangDef) {
             initialize_vars_and_statics(namespace_env(env, Match(stmt->ast, LangDef)->name),
                                         Match(stmt->ast, LangDef)->namespace);
+        } else if (stmt->ast->tag == Extend) {
+            initialize_vars_and_statics(namespace_env(env, Match(stmt->ast, Extend)->name),
+                                        Match(stmt->ast, Extend)->body);
         } else if (stmt->ast->tag == Use) {
             continue;
         } else {
@@ -4348,6 +4348,9 @@ CORD compile_statement_type_header(env_t *env, Path_t header_path, ast_t *ast)
             "extern const TypeInfo_t ", full_name, ";\n"
         );
     }
+    case Extend: {
+        return CORD_EMPTY;
+    }
     default:
         return CORD_EMPTY;
     }
@@ -4364,6 +4367,12 @@ CORD compile_statement_namespace_header(env_t *env, Path_t header_path, ast_t *a
         block = def->namespace;
         break;
     }
+    case Extend: {
+        auto extend = Match(ast, Extend);
+        ns_name = extend->name;
+        block = extend->body;
+        break;
+    }
     case StructDef: {
         auto def = Match(ast, StructDef);
         ns_name = def->name;
diff --git a/src/environment.c b/src/environment.c
index 776e7852..6822502a 100644
--- a/src/environment.c
+++ b/src/environment.c
@@ -13,7 +13,6 @@
 #include "typecheck.h"
 
 type_t *TEXT_TYPE = NULL;
-type_t *MATCH_TYPE = NULL;
 type_t *RNG_TYPE = NULL;
 public type_t *PATH_TYPE = NULL;
 public type_t *PATH_TYPE_TYPE = NULL;
@@ -67,7 +66,6 @@ env_t *global_env(void)
     (void)bind_type(env, "Int32", Type(IntType, .bits=TYPE_IBITS32));
     (void)bind_type(env, "Memory", Type(MemoryType));
     PATH_TYPE_TYPE = declare_type(env, "enum PathType(Relative, Absolute, Home)");
-    MATCH_TYPE = declare_type(env, "struct Match(text:Text, index:Int, captures:[Text])");
     PATH_TYPE = declare_type(env, "struct Path(type:PathType, components:[Text])");
     RNG_TYPE = declare_type(env, "struct RNG(state:@Memory)");
 
@@ -279,13 +277,6 @@ env_t *global_env(void)
 #undef F_opt
 #undef F
 #undef C
-        {"Match", MATCH_TYPE, "Match_t", "Match", TypedArray(ns_entry_t,
-             // No methods
-        )},
-        {"Pattern", Type(TextType, .lang="Pattern", .env=namespace_env(env, "Pattern")), "Pattern_t", "Pattern$info", TypedArray(ns_entry_t,
-            {"escape_int", "Int$value_as_text", "func(i:Int -> Pattern)"},
-            {"escape_text", "Pattern$escape_text", "func(text:Text -> Pattern)"},
-        )},
         {"PathType", PATH_TYPE_TYPE, "PathType_t", "PathType$info", TypedArray(ns_entry_t,
             {"Relative", "((PathType_t){.$tag=PATH_RELATIVE})", "PathType"},
             {"Absolute", "((PathType_t){.$tag=PATH_ABSOLUTE})", "PathType"},
@@ -353,44 +344,42 @@ env_t *global_env(void)
             {"as_c_string", "Text$as_c_string", "func(text:Text -> CString)"},
             {"at", "Text$cluster", "func(text:Text, index:Int -> Text)"},
             {"by_line", "Text$by_line", "func(text:Text -> func(->Text?))"},
-            {"by_match", "Text$by_match", "func(text:Text, pattern:Pattern -> func(->Match?))"},
-            {"by_split", "Text$by_split", "func(text:Text, pattern=$Pattern'' -> func(->Text?))"},
+            {"by_split", "Text$by_split", "func(text:Text, delimiter='' -> func(->Text?))"},
+            {"by_split_any", "Text$by_split_any", "func(text:Text, delimiters=\" $\\t\\r\\n\" -> func(->Text?))"},
             {"bytes", "Text$utf8_bytes", "func(text:Text -> [Byte])"},
             {"caseless_equals", "Text$equal_ignoring_case", "func(a,b:Text, language='C' -> Bool)"},
             {"codepoint_names", "Text$codepoint_names", "func(text:Text -> [Text])"},
             {"ends_with", "Text$ends_with", "func(text,suffix:Text -> Bool)"},
-            {"each", "Text$each", "func(text:Text, pattern:Pattern, fn:func(match:Match), recursive=yes)"},
-            {"find", "Text$find", "func(text:Text, pattern:Pattern, start=1 -> Match?)"},
-            {"find_all", "Text$find_all", "func(text:Text, pattern:Pattern -> [Match])"},
             {"from", "Text$from", "func(text:Text, first:Int -> Text)"},
             {"from_bytes", "Text$from_bytes", "func(bytes:[Byte] -> Text?)"},
             {"from_c_string", "Text$from_str", "func(str:CString -> Text?)"},
             {"from_codepoint_names", "Text$from_codepoint_names", "func(codepoint_names:[Text] -> Text?)"},
             {"from_codepoints", "Text$from_codepoints", "func(codepoints:[Int32] -> Text)"},
             {"from_text", "Path$from_text", "func(text:Text -> Path)"},
-            {"has", "Text$has", "func(text:Text, pattern:Pattern -> Bool)"},
+            {"has", "Text$has", "func(text:Text, target:Text -> Bool)"},
             {"join", "Text$join", "func(glue:Text, pieces:[Text] -> Text)"},
             {"left_pad", "Text$left_pad", "func(text:Text, count:Int, pad=' ', language='C' -> Text)"},
             {"lines", "Text$lines", "func(text:Text -> [Text])"},
             {"lower", "Text$lower", "func(text:Text, language='C' -> Text)"},
-            {"map", "Text$map", "func(text:Text, pattern:Pattern, fn:func(match:Match -> Text), recursive=yes -> Text)"},
-            {"matches", "Text$matches", "func(text:Text, pattern:Pattern -> [Text]?)"},
             {"middle_pad", "Text$middle_pad", "func(text:Text, count:Int, pad=' ', language='C' -> Text)"},
             {"quoted", "Text$quoted", "func(text:Text, color=no, quotation_mark='\"' -> Text)"},
             {"repeat", "Text$repeat", "func(text:Text, count:Int -> Text)"},
-            {"replace", "Text$replace", "func(text:Text, pattern:Pattern, replacement:Text, backref=$/\\/, recursive=yes -> Text)"},
-            {"replace_all", "Text$replace_all", "func(text:Text, replacements:{Pattern,Text}, backref=$/\\/, recursive=yes -> Text)"},
+            {"replace", "Text$replace", "func(text:Text, target:Text, replacement:Text -> Text)"},
             {"reversed", "Text$reversed", "func(text:Text -> Text)"},
             {"right_pad", "Text$right_pad", "func(text:Text, count:Int, pad=' ', language='C' -> Text)"},
             {"slice", "Text$slice", "func(text:Text, from=1, to=-1 -> Text)"},
-            {"split", "Text$split", "func(text:Text, pattern=$Pattern'' -> [Text])"},
+            {"split", "Text$split", "func(text:Text, delimiter='' -> [Text])"},
+            {"split_any", "Text$split_any", "func(text:Text, delimiters=\" $\\t\\r\\n\" -> [Text])"},
             {"starts_with", "Text$starts_with", "func(text,prefix:Text -> Bool)"},
             {"title", "Text$title", "func(text:Text, language='C' -> Text)"},
             {"to", "Text$to", "func(text:Text, last:Int -> Text)"},
-            {"trim", "Text$trim", "func(text:Text, pattern=$/{whitespace}/, trim_left=yes, trim_right=yes -> Text)"},
+            {"translate", "Text$translate", "func(text:Text, translations:{Text,Text} -> Text)"},
+            {"trim", "Text$trim", "func(text:Text, to_trim=\" \t\r\n\", left=yes, right=yes -> Text)"},
             {"upper", "Text$upper", "func(text:Text, language='C' -> Text)"},
             {"utf32_codepoints", "Text$utf32_codepoints", "func(text:Text -> [Int32])"},
             {"width", "Text$width", "func(text:Text, language='C' -> Int)"},
+            {"without_prefix", "Text$without_prefix", "func(text,prefix:Text -> Text)"},
+            {"without_suffix", "Text$without_suffix", "func(text,suffix:Text -> Text)"},
         )},
     };
 
@@ -518,9 +507,6 @@ env_t *global_env(void)
                      {"Num32$from_int64", "func(i:Int64, truncate=no -> Num32)"},
                      {"Num32$from_int", "func(i:Int, truncate=no -> Num32)"},
                      {"Num32$from_num", "func(n:Num -> Num32)"});
-    ADD_CONSTRUCTORS("Pattern",
-                     {"Pattern$escape_text", "func(text:Text -> Pattern)"},
-                     {"Int$value_as_text", "func(i:Int -> Pattern)"});
     ADD_CONSTRUCTORS("Path",
                      {"Path$escape_text", "func(text:Text -> Path)"},
                      {"Path$escape_path", "func(path:Path -> Path)"},
@@ -534,11 +520,6 @@ env_t *global_env(void)
                      .ret=PATH_TYPE),
                 "Path$from_text");
 
-    set_binding(namespace_env(env, "Pattern"), "from_text",
-                Type(FunctionType, .args=new(arg_t, .name="text", .type=TEXT_TYPE),
-                     .ret=Type(TextType, .lang="Pattern", .env=namespace_env(env, "Pattern"))),
-                "(Pattern_t)");
-
     struct {
         const char *name, *code, *type_str;
     } global_vars[] = {
diff --git a/src/environment.h b/src/environment.h
index 95e3c3e1..00b8fbba 100644
--- a/src/environment.h
+++ b/src/environment.h
@@ -89,7 +89,6 @@ void set_binding(env_t *env, const char *name, type_t *type, CORD code);
 binding_t *get_namespace_binding(env_t *env, ast_t *self, const char *name);
 #define code_err(ast, ...) compiler_err((ast)->file, (ast)->start, (ast)->end, __VA_ARGS__)
 extern type_t *TEXT_TYPE;
-extern type_t *MATCH_TYPE;
 extern type_t *RNG_TYPE;
 extern type_t *PATH_TYPE;
 extern type_t *PATH_TYPE_TYPE;
diff --git a/src/parse.c b/src/parse.c
index 14221cc0..2e3e2ece 100644
--- a/src/parse.c
+++ b/src/parse.c
@@ -22,7 +22,6 @@
 #include "ast.h"
 #include "cordhelpers.h"
 #include "stdlib/integers.h"
-#include "stdlib/patterns.h"
 #include "stdlib/paths.h"
 #include "stdlib/print.h"
 #include "stdlib/stdlib.h"
@@ -64,7 +63,7 @@ int op_tightness[] = {
 static const char *keywords[] = {
     "yes", "xor", "while", "when", "use", "unless", "struct", "stop", "skip", "return",
     "or", "not", "none", "no", "mod1", "mod", "pass", "lang", "inline", "in", "if",
-    "func", "for", "extern", "enum", "else", "do", "deserialize", "defer", "and",
+    "func", "for", "extern", "extend", "enum", "else", "do", "deserialize", "defer", "and",
     "_min_", "_max_", NULL,
 };
 
@@ -120,6 +119,7 @@ static PARSER(parse_inline_c);
 static PARSER(parse_int);
 static PARSER(parse_lambda);
 static PARSER(parse_lang_def);
+static PARSER(parse_extend);
 static PARSER(parse_namespace);
 static PARSER(parse_negative);
 static PARSER(parse_not);
@@ -1241,9 +1241,6 @@ PARSER(parse_text) {
         open_quote = *pos;
         ++pos;
         close_quote = closing[(int)open_quote] ? closing[(int)open_quote] : open_quote;
-
-        if (!lang && (open_quote == '/' || open_quote == '|'))
-            lang = "Pattern";
     } else {
         return NULL;
     }
@@ -1904,9 +1901,10 @@ PARSER(parse_namespace) {
         if (get_indent(ctx, next) != indent) break;
         ast_t *stmt;
         if ((stmt=optional(ctx, &pos, parse_struct_def))
+            ||(stmt=optional(ctx, &pos, parse_func_def))
             ||(stmt=optional(ctx, &pos, parse_enum_def))
             ||(stmt=optional(ctx, &pos, parse_lang_def))
-            ||(stmt=optional(ctx, &pos, parse_func_def))
+            ||(stmt=optional(ctx, &pos, parse_extend))
             ||(stmt=optional(ctx, &pos, parse_convert_def))
             ||(stmt=optional(ctx, &pos, parse_use))
             ||(stmt=optional(ctx, &pos, parse_extern))
@@ -1940,9 +1938,10 @@ PARSER(parse_file_body) {
         if (get_indent(ctx, next) != 0) break;
         ast_t *stmt;
         if ((stmt=optional(ctx, &pos, parse_struct_def))
+            ||(stmt=optional(ctx, &pos, parse_func_def))
             ||(stmt=optional(ctx, &pos, parse_enum_def))
             ||(stmt=optional(ctx, &pos, parse_lang_def))
-            ||(stmt=optional(ctx, &pos, parse_func_def))
+            ||(stmt=optional(ctx, &pos, parse_extend))
             ||(stmt=optional(ctx, &pos, parse_convert_def))
             ||(stmt=optional(ctx, &pos, parse_use))
             ||(stmt=optional(ctx, &pos, parse_extern))
@@ -2112,6 +2111,32 @@ PARSER(parse_lang_def) {
     return NewAST(ctx->file, start, pos, LangDef, .name=name, .namespace=namespace);
 }
 
+PARSER(parse_extend) {
+    const char *start = pos;
+    // extend Name: body...
+    if (!match_word(&pos, "extend")) return NULL;
+    int64_t starting_indent = get_indent(ctx, pos);
+    spaces(&pos);
+    const char *name = get_id(&pos);
+    if (!name)
+        parser_err(ctx, start, pos, "I expected a name for this lang");
+
+    ast_t *body = NULL;
+    if (match(&pos, ":")) {
+        const char *ns_pos = pos;
+        whitespace(&ns_pos);
+        int64_t ns_indent = get_indent(ctx, ns_pos);
+        if (ns_indent > starting_indent) {
+            pos = ns_pos;
+            body = optional(ctx, &pos, parse_namespace);
+        }
+    }
+    if (!body)
+        body = NewAST(ctx->file, pos, pos, Block, .statements=NULL);
+
+    return NewAST(ctx->file, start, pos, Extend, .name=name, .body=body);
+}
+
 arg_ast_t *parse_args(parse_ctx_t *ctx, const char **pos)
 {
     arg_ast_t *args = NULL;
@@ -2373,20 +2398,6 @@ PARSER(parse_use) {
         what = USE_LOCAL;
     } else {
         what = USE_MODULE;
-
-        // When `use`ing a URL, convert it to a hash:
-        Text_t text = Text$from_str(name);
-        Array_t m = Text$matches(text, Pattern("{url}"));
-        if (m.length >= 0) {
-            text = Text$trim(text, Pattern("http{0-1 s}://"), true, false);
-            FILE *shasum = popen(String("echo -n '", text, "' | sha256sum"), "r");
-            const size_t HASH_LEN = 32;
-            char *hash = GC_MALLOC_ATOMIC(HASH_LEN + 1);
-            size_t just_read = fread(hash, sizeof(char), HASH_LEN, shasum);
-            if (just_read < HASH_LEN)
-                print_err("Failed to get SHA sum for 'use': ", name);
-            name = hash;
-        }
     }
     return NewAST(ctx->file, start, pos, Use, .var=var, .path=name, .what=what);
 }
diff --git a/src/stdlib/README.md b/src/stdlib/README.md
index 6591ead6..1c72d3d3 100644
--- a/src/stdlib/README.md
+++ b/src/stdlib/README.md
@@ -27,7 +27,6 @@ some common functionality.
 - Nums: [nums.h](nums.h), [nums.c](nums.c)
 - Optionals: [optionals.h](optionals.h), [optionals.c](optionals.c)
 - Paths: [paths.h](paths.h), [paths.c](paths.c)
-- Patterns: [patterns.h](patterns.h), [patterns.c](patterns.c)
 - Pointers: [pointers.h](pointers.h), [pointers.c](pointers.c)
 - Tables: [tables.h](tables.h), [tables.c](tables.c)
 - Text: [text.h](text.h), [text.c](text.c)
diff --git a/src/stdlib/datatypes.h b/src/stdlib/datatypes.h
index b1265fc3..26bd9c3c 100644
--- a/src/stdlib/datatypes.h
+++ b/src/stdlib/datatypes.h
@@ -94,9 +94,6 @@ typedef struct Text_s {
     };
 } Text_t;
 
-#define Pattern_t Text_t
-#define OptionalPattern_t Text_t
-
 typedef struct {
     enum { PATH_NONE, PATH_RELATIVE, PATH_ABSOLUTE, PATH_HOME } $tag;
 } PathType_t;
diff --git a/src/stdlib/optionals.c b/src/stdlib/optionals.c
index 797cb111..d3309029 100644
--- a/src/stdlib/optionals.c
+++ b/src/stdlib/optionals.c
@@ -6,7 +6,6 @@
 #include "integers.h"
 #include "metamethods.h"
 #include "nums.h"
-#include "patterns.h"
 #include "text.h"
 #include "util.h"
 
diff --git a/src/stdlib/paths.c b/src/stdlib/paths.c
index 05575620..3f27aef7 100644
--- a/src/stdlib/paths.c
+++ b/src/stdlib/paths.c
@@ -24,7 +24,6 @@
 #include "integers.h"
 #include "optionals.h"
 #include "paths.h"
-#include "patterns.h"
 #include "structs.h"
 #include "text.h"
 #include "types.h"
@@ -599,15 +598,10 @@ public PUREFUNC Text_t Path$base_name(Path_t path)
 
 public Text_t Path$extension(Path_t path, bool full)
 {
-    Text_t base = Path$base_name(path);
-    Array_t results = Text$matches(base, full ? Pattern(".{!.}.{..}") : Pattern(".{..}.{!.}{end}"));
-    if (results.length > 0)
-        return *((Text_t*)(results.data + results.stride*1));
-    results = Text$matches(base, full ? Pattern("{!.}.{..}") : Pattern("{..}.{!.}{end}"));
-    if (results.length > 0)
-        return *((Text_t*)(results.data + results.stride*1));
-    else
-        return Text("");
+    const char *base = Text$as_c_string(Path$base_name(path));
+    const char *dot = full ? strchr(base + 1, '.') : strrchr(base + 1, '.');
+    const char *extension = dot ? dot + 1 : "";
+    return Text$from_str(extension);
 }
 
 public Path_t Path$with_component(Path_t path, Text_t component)
@@ -635,10 +629,10 @@ public Path_t Path$with_extension(Path_t path, Text_t extension, bool replace)
     Text_t last = *(Text_t*)(path.components.data + path.components.stride*(path.components.length-1));
     Array$remove_at(&result.components, I(-1), I(1), sizeof(Text_t));
     if (replace) {
-        if (Text$starts_with(last, Text(".")))
-            last = Text$replace(last, Pattern(".{!.}.{..}"), Text(".@1"), Pattern("@"), false);
-        else
-            last = Text$replace(last, Pattern("{!.}.{..}"), Text("@1"), Pattern("@"), false);
+        const char *base = Text$as_c_string(last);
+        const char *dot = strchr(base + 1, '.');
+        if (dot)
+            last = Text$from_strn(base, (size_t)(dot - base));
     }
 
     last = Text$concat(last, extension);
diff --git a/src/stdlib/patterns.c b/src/stdlib/patterns.c
deleted file mode 100644
index b7891f88..00000000
--- a/src/stdlib/patterns.c
+++ /dev/null
@@ -1,1337 +0,0 @@
-// Logic for text pattern matching
-
-#include <ctype.h>
-#include <sys/param.h>
-#include <unictype.h>
-#include <uniname.h>
-#include <unistring/version.h>
-
-#include "arrays.h"
-#include "integers.h"
-#include "optionals.h"
-#include "patterns.h"
-#include "structs.h"
-#include "tables.h"
-#include "text.h"
-#include "types.h"
-
-#define MAX_BACKREFS 100
-
-typedef struct {
-    int64_t index, length;
-    bool occupied, recursive;
-} capture_t;
-
-typedef struct {
-    enum { PAT_START, PAT_END, PAT_ANY, PAT_GRAPHEME, PAT_PROPERTY, PAT_QUOTE, PAT_PAIR, PAT_FUNCTION } tag;
-    bool negated, non_capturing;
-    int64_t min, max;
-    union {
-        int32_t grapheme;
-        uc_property_t property;
-        int64_t (*fn)(TextIter_t *, int64_t);
-        int32_t quote_graphemes[2];
-        int32_t pair_graphemes[2];
-    };
-} pat_t;
-
-static Text_t Text$replace_array(Text_t text, Array_t replacements, Text_t backref_pat, bool recursive);
-
-static INLINE void skip_whitespace(TextIter_t *state, int64_t *i)
-{
-    while (*i < state->stack[0].text.length) {
-        int32_t grapheme = Text$get_grapheme_fast(state, *i);
-        if (grapheme > 0 && !uc_is_property_white_space((ucs4_t)grapheme))
-            return;
-        *i += 1;
-    }
-}
-
-static INLINE bool match_grapheme(TextIter_t *state, int64_t *i, int32_t grapheme)
-{
-    if (*i < state->stack[0].text.length && Text$get_grapheme_fast(state, *i) == grapheme) {
-        *i += 1;
-        return true;
-    }
-    return false;
-}
-
-static INLINE bool match_str(TextIter_t *state, int64_t *i, const char *str)
-{
-    int64_t matched = 0;
-    while (matched[str]) {
-        if (*i + matched >= state->stack[0].text.length || Text$get_grapheme_fast(state, *i + matched) != str[matched])
-            return false;
-        matched += 1;
-    }
-    *i += matched;
-    return true;
-}
-
-static int64_t parse_int(TextIter_t *state, int64_t *i)
-{
-    int64_t value = 0;
-    for (;; *i += 1) {
-        uint32_t grapheme = Text$get_main_grapheme_fast(state, *i);
-        int digit = uc_digit_value(grapheme);
-        if (digit < 0) break;
-        if (value >= INT64_MAX/10) break;
-        value = 10*value + digit;
-    }
-    return value;
-}
-
-static const char *get_property_name(TextIter_t *state, int64_t *i)
-{
-    skip_whitespace(state, i);
-    char *name = GC_MALLOC_ATOMIC(UNINAME_MAX);
-    char *dest = name;
-    while (*i < state->stack[0].text.length) {
-        int32_t grapheme = Text$get_grapheme_fast(state, *i);
-        if (!(grapheme & ~0xFF) && (isalnum(grapheme) || grapheme == ' ' || grapheme == '_' || grapheme == '-')) {
-            *dest = (char)grapheme;
-            ++dest;
-            if (dest >= name + UNINAME_MAX - 1)
-                break;
-        } else {
-            break;
-        }
-        *i += 1;
-    }
-
-    while (dest > name && dest[-1] == ' ')
-        *(dest--) = '\0';
-
-    if (dest == name) return NULL;
-    *dest = '\0';
-    return name;
-}
-
-#define EAT1(state, index, cond) ({\
-        int32_t grapheme = Text$get_grapheme_fast(state, index); \
-        bool success = (cond); \
-        if (success) index += 1; \
-        success; })
-
-#define EAT2(state, index, cond1, cond2) ({\
-        int32_t grapheme = Text$get_grapheme_fast(state, index); \
-        bool success = (cond1); \
-        if (success) { \
-            grapheme = Text$get_grapheme_fast(state, index + 1); \
-            success = (cond2); \
-            if (success) \
-                index += 2; \
-        } \
-        success; })
-
-
-#define EAT_MANY(state, index, cond) ({ int64_t _n = 0; while (EAT1(state, index, cond)) { _n += 1; } _n; })
-
-static int64_t match_email(TextIter_t *state, int64_t index)
-{
-    // email = local "@" domain
-    // local = 1-64 ([a-zA-Z0-9!#$%&‘*+–/=?^_`.{|}~] | non-ascii)
-    // domain = dns-label ("." dns-label)*
-    // dns-label = 1-63 ([a-zA-Z0-9-] | non-ascii)
-
-    if (index > 0) {
-        uint32_t prev_codepoint = Text$get_main_grapheme_fast(state, index - 1);
-        if (uc_is_property_alphabetic(prev_codepoint))
-            return -1;
-    }
-
-    int64_t start_index = index;
-
-    // Local part:
-    int64_t local_len = 0;
-    static const char *allowed_local = "!#$%&‘*+–/=?^_`.{|}~";
-    while (EAT1(state, index,
-                (grapheme & ~0x7F) || isalnum((char)grapheme) || strchr(allowed_local, (char)grapheme))) {
-        local_len += 1;
-        if (local_len > 64) return -1;
-    }
-    
-    if (!EAT1(state, index, grapheme == '@'))
-        return -1;
-
-    // Host
-    int64_t host_len = 0;
-    do {
-        int64_t label_len = 0;
-        while (EAT1(state, index,
-                    (grapheme & ~0x7F) || isalnum((char)grapheme) || grapheme == '-')) {
-            label_len += 1;
-            if (label_len > 63) return -1;
-        }
-
-        if (label_len == 0)
-            return -1;
-
-        host_len += label_len;
-        if (host_len > 255)
-            return -1;
-        host_len += 1;
-    } while (EAT1(state, index, grapheme == '.'));
-
-    return index - start_index;
-}
-
-static int64_t match_ipv6(TextIter_t *state, int64_t index)
-{
-    if (index > 0) {
-        int32_t prev_codepoint = Text$get_grapheme_fast(state, index - 1);
-        if ((prev_codepoint & ~0x7F) && (isxdigit(prev_codepoint) || prev_codepoint == ':'))
-            return -1;
-    }
-    int64_t start_index = index;
-    const int NUM_CLUSTERS = 8;
-    bool double_colon_used = false;
-    for (int cluster = 0; cluster < NUM_CLUSTERS; cluster++) {
-        for (int digits = 0; digits < 4; digits++) {
-            if (!EAT1(state, index, ~(grapheme & ~0x7F) && isxdigit((char)grapheme)))
-                break;
-        }
-        if (EAT1(state, index, ~(grapheme & ~0x7F) && isxdigit((char)grapheme)))
-            return -1; // Too many digits
-
-        if (cluster == NUM_CLUSTERS-1) {
-            break;
-        } else if (!EAT1(state, index, grapheme == ':')) {
-            if (double_colon_used)
-                break;
-            return -1;
-        }
-
-        if (EAT1(state, index, grapheme == ':')) {
-            if (double_colon_used)
-                return -1;
-            double_colon_used = true;
-        }
-    }
-    return index - start_index;
-}
-
-static int64_t match_ipv4(TextIter_t *state, int64_t index)
-{
-    if (index > 0) {
-        int32_t prev_codepoint = Text$get_grapheme_fast(state, index - 1);
-        if ((prev_codepoint & ~0x7F) && (isdigit(prev_codepoint) || prev_codepoint == '.'))
-            return -1;
-    }
-    int64_t start_index = index;
-
-    const int NUM_CLUSTERS = 4;
-    for (int cluster = 0; cluster < NUM_CLUSTERS; cluster++) {
-        for (int digits = 0; digits < 3; digits++) {
-            if (!EAT1(state, index, ~(grapheme & ~0x7F) && isdigit((char)grapheme))) {
-                if (digits == 0) return -1;
-                break;
-            }
-        }
-
-        if (EAT1(state, index, ~(grapheme & ~0x7F) && isdigit((char)grapheme)))
-            return -1; // Too many digits
-
-        if (cluster == NUM_CLUSTERS-1)
-            break;
-        else if (!EAT1(state, index, grapheme == '.'))
-            return -1;
-    }
-    return (index - start_index);
-}
-
-static int64_t match_ip(TextIter_t *state, int64_t index)
-{
-    int64_t len = match_ipv6(state, index);
-    if (len >= 0) return len;
-    len = match_ipv4(state, index);
-    return (len >= 0) ? len : -1;
-}
-
-static int64_t match_host(TextIter_t *state, int64_t index)
-{
-    int64_t ip_len = match_ip(state, index);
-    if (ip_len > 0) return ip_len;
-
-    int64_t start_index = index;
-    if (match_grapheme(state, &index, '[')) {
-        ip_len = match_ip(state, index);
-        if (ip_len <= 0) return -1;
-        index += ip_len;
-        if (match_grapheme(state, &index, ']'))
-            return (index - start_index);
-        return -1;
-    }
-
-    if (!EAT1(state, index, isalpha(grapheme)))
-        return -1;
-
-    static const char *non_host_chars = "/#?:@ \t\r\n<>[]{}\\^|\"`";
-    EAT_MANY(state, index, (grapheme & ~0x7F) || !strchr(non_host_chars, (char)grapheme));
-    return (index - start_index);
-}
-
-static int64_t match_authority(TextIter_t *state, int64_t index)
-{
-    int64_t authority_start = index;
-    static const char *non_segment_chars = "/#?:@ \t\r\n<>[]{}\\^|\"`.";
-
-    // Optional user@ prefix:
-    int64_t username_len = EAT_MANY(state, index, (grapheme & ~0x7F) || !strchr(non_segment_chars, (char)grapheme));
-    if (username_len < 1 || !EAT1(state, index, grapheme == '@'))
-        index = authority_start; // No user@ part
-
-    // Host:
-    int64_t host_len = match_host(state, index);
-    if (host_len <= 0) return -1;
-    index += host_len;
-
-    // Port:
-    if (EAT1(state, index, grapheme == ':')) {
-        if (EAT_MANY(state, index, !(grapheme & ~0x7F) && isdigit(grapheme)) == 0)
-            return -1;
-    }
-    return (index - authority_start);
-}
-
-static int64_t match_uri(TextIter_t *state, int64_t index)
-{
-    // URI = scheme ":" ["//" authority] path ["?" query] ["#" fragment]
-    // scheme = [a-zA-Z] [a-zA-Z0-9+.-]
-    // authority = [userinfo "@"] host [":" port]
-
-    if (index > 0) {
-        // Don't match if we're not at a word edge:
-        uint32_t prev_codepoint = Text$get_main_grapheme_fast(state, index - 1);
-        if (uc_is_property_alphabetic(prev_codepoint))
-            return -1;
-    }
-
-    int64_t start_index = index;
-
-    // Scheme:
-    if (!EAT1(state, index, isalpha(grapheme)))
-        return -1;
-    EAT_MANY(state, index, !(grapheme & ~0x7F) && (isalnum(grapheme) || grapheme == '+' || grapheme == '.' || grapheme == '-'));
-    if (!match_grapheme(state, &index, ':'))
-        return -1;
-
-    // Authority:
-    int64_t authority_len;
-    if (match_str(state, &index, "//")) {
-        authority_len = match_authority(state, index);
-        if (authority_len > 0)
-            index += authority_len;
-    } else {
-        authority_len = 0;
-    }
-
-    // Path:
-    int64_t path_start = index;
-    if (EAT1(state, index, grapheme == '/') || authority_len <= 0) {
-        static const char *non_path = " \"#?<>[]{}\\^`|";
-        EAT_MANY(state, index, (grapheme & ~0x7F) || !strchr(non_path, (char)grapheme));
-
-        if (EAT1(state, index, grapheme == '?')) { // Query
-            static const char *non_query = " \"#<>[]{}\\^`|";
-            EAT_MANY(state, index, (grapheme & ~0x7F) || !strchr(non_query, (char)grapheme));
-        }
-        
-        if (EAT1(state, index, grapheme == '#')) { // Fragment
-            static const char *non_fragment = " \"#<>[]{}\\^`|";
-            EAT_MANY(state, index, (grapheme & ~0x7F) || !strchr(non_fragment, (char)grapheme));
-        }
-    }
-
-    if (authority_len <= 0 && index == path_start)
-        return -1;
-
-    return index - start_index;
-}
-
-static int64_t match_url(TextIter_t *state, int64_t index)
-{
-    int64_t lookahead = index;
-    if (!(match_str(state, &lookahead, "https:")
-        || match_str(state, &lookahead, "http:")
-        || match_str(state, &lookahead, "ftp:")
-        || match_str(state, &lookahead, "wss:")
-        || match_str(state, &lookahead, "ws:")))
-        return -1;
-
-    return match_uri(state, index);
-}
-
-static int64_t match_id(TextIter_t *state, int64_t index)
-{
-    if (!EAT1(state, index, uc_is_property((ucs4_t)grapheme, UC_PROPERTY_XID_START)))
-        return -1;
-    return 1 + EAT_MANY(state, index, uc_is_property((ucs4_t)grapheme, UC_PROPERTY_XID_CONTINUE));
-}
-
-static int64_t match_int(TextIter_t *state, int64_t index)
-{
-    int64_t negative = EAT1(state, index, grapheme == '-') ? 1 : 0;
-    int64_t len = EAT_MANY(state, index, uc_is_property((ucs4_t)grapheme, UC_PROPERTY_DECIMAL_DIGIT));
-    return len > 0 ? negative + len : -1;
-}
-
-static int64_t match_alphanumeric(TextIter_t *state, int64_t index)
-{
-    return EAT1(state, index, uc_is_property_alphabetic((ucs4_t)grapheme) || uc_is_property_numeric((ucs4_t)grapheme))
-        ? 1 : -1;
-}
-
-static int64_t match_num(TextIter_t *state, int64_t index)
-{
-    bool negative = EAT1(state, index, grapheme == '-') ? 1 : 0;
-    int64_t pre_decimal = EAT_MANY(state, index,
-                                   uc_is_property((ucs4_t)grapheme, UC_PROPERTY_DECIMAL_DIGIT));
-    bool decimal = (EAT1(state, index, grapheme == '.') == 1);
-    int64_t post_decimal = decimal ? EAT_MANY(state, index,
-                                              uc_is_property((ucs4_t)grapheme, UC_PROPERTY_DECIMAL_DIGIT)) : 0;
-    if (pre_decimal == 0 && post_decimal == 0)
-        return -1;
-    return negative + pre_decimal + decimal + post_decimal;
-}
-
-static int64_t match_newline(TextIter_t *state, int64_t index)
-{
-    if (index >= state->stack[0].text.length)
-        return -1;
-
-    uint32_t grapheme = index >= state->stack[0].text.length ? 0 : Text$get_main_grapheme_fast(state, index);
-    if (grapheme == '\n')
-        return 1;
-    if (grapheme == '\r' && Text$get_grapheme_fast(state, index + 1) == '\n')
-        return 2;
-    return -1;
-}
-
-static int64_t match_pat(TextIter_t *state, int64_t index, pat_t pat)
-{
-    Text_t text = state->stack[0].text;
-    int32_t grapheme = index >= text.length ? 0 : Text$get_grapheme_fast(state, index);
-
-    switch (pat.tag) {
-    case PAT_START: {
-        if (index == 0)
-            return pat.negated ? -1 : 0;
-        return pat.negated ? 0 : -1;
-    }
-    case PAT_END: {
-        if (index >= text.length)
-            return pat.negated ? -1 : 0;
-        return pat.negated ? 0 : -1;
-    }
-    case PAT_ANY: {
-        assert(!pat.negated);
-        return (index < text.length) ? 1 : -1;
-    }
-    case PAT_GRAPHEME: {
-        if (index >= text.length)
-            return -1;
-        else if (grapheme == pat.grapheme)
-            return pat.negated ? -1 : 1;
-        return pat.negated ? 1 : -1;
-    }
-    case PAT_PROPERTY: {
-        if (index >= text.length)
-            return -1;
-        else if (uc_is_property((ucs4_t)grapheme, pat.property))
-            return pat.negated ? -1 : 1;
-        return pat.negated ? 1 : -1;
-    }
-    case PAT_PAIR: {
-        // Nested punctuation: (?), [?], etc
-        if (index >= text.length)
-            return -1;
-
-        int32_t open = pat.pair_graphemes[0];
-        if (grapheme != open)
-            return pat.negated ? 1 : -1;
-
-        int32_t close = pat.pair_graphemes[1];
-        int64_t depth = 1;
-        int64_t match_len = 1;
-        for (; depth > 0; match_len++) {
-            if (index + match_len >= text.length)
-                return pat.negated ? 1 : -1;
-
-            int32_t c = Text$get_grapheme_fast(state, index + match_len);
-            if (c == open)
-                depth += 1;
-            else if (c == close)
-                depth -= 1;
-        }
-        return pat.negated ? -1 : match_len;
-    }
-    case PAT_QUOTE: {
-        // Nested quotes: "?", '?', etc
-        if (index >= text.length)
-            return -1;
-
-        int32_t open = pat.quote_graphemes[0];
-        if (grapheme != open)
-            return pat.negated ? 1 : -1;
-
-        int32_t close = pat.quote_graphemes[1];
-        for (int64_t i = index + 1; i < text.length; i++) {
-            int32_t c = Text$get_grapheme_fast(state, i);
-            if (c == close) {
-                return pat.negated ? -1 : (i - index) + 1;
-            } else if (c == '\\' && index + 1 < text.length) {
-                i += 1; // Skip ahead an extra step
-            }
-        }
-        return pat.negated ? 1 : -1;
-    }
-    case PAT_FUNCTION: {
-        int64_t match_len = pat.fn(state, index);
-        if (match_len >= 0)
-            return pat.negated ? -1 : match_len;
-        return pat.negated ? 1 : -1;
-    }
-    default: errx(1, "Invalid pattern");
-    }
-    errx(1, "Unreachable");
-}
-
-static pat_t parse_next_pat(TextIter_t *state, int64_t *index)
-{
-    if (EAT2(state, *index,
-             uc_is_property((ucs4_t)grapheme, UC_PROPERTY_QUOTATION_MARK),
-             grapheme == '?')) {
-        // Quotations: "?", '?', etc
-        int32_t open = Text$get_grapheme_fast(state, *index-2);
-        int32_t close = open;
-        uc_mirror_char((ucs4_t)open, (ucs4_t*)&close);
-        if (!match_grapheme(state, index, close))
-            fail("Pattern's closing quote is missing: ", state->stack[0].text);
-
-        return (pat_t){
-            .tag=PAT_QUOTE,
-            .min=1, .max=1,
-            .quote_graphemes={open, close},
-        };
-    } else if (EAT2(state, *index,
-                    uc_is_property((ucs4_t)grapheme, UC_PROPERTY_PAIRED_PUNCTUATION),
-                    grapheme == '?')) {
-        // Nested punctuation: (?), [?], etc
-        int32_t open = Text$get_grapheme_fast(state, *index-2);
-        int32_t close = open;
-        uc_mirror_char((ucs4_t)open, (ucs4_t*)&close);
-        if (!match_grapheme(state, index, close))
-            fail("Pattern's closing brace is missing: ", state->stack[0].text);
-        
-        return (pat_t){
-            .tag=PAT_PAIR,
-            .min=1, .max=1,
-            .pair_graphemes={open, close},
-        };
-    } else if (EAT1(state, *index, grapheme == '{')) { // named patterns {id}, {2-3 hex}, etc.
-        skip_whitespace(state, index);
-        int64_t min, max;
-        if (uc_is_digit((ucs4_t)Text$get_grapheme_fast(state, *index))) {
-            min = parse_int(state, index);
-            skip_whitespace(state, index);
-            if (match_grapheme(state, index, '+')) {
-                max = INT64_MAX;
-            } else if (match_grapheme(state, index, '-')) {
-                max = parse_int(state, index);
-            } else {
-                max = min;
-            }
-            if (min > max) fail("Minimum repetitions (", min, ") is less than the maximum (", max, ")");
-        } else {
-            min = -1, max = -1;
-        }
-
-        skip_whitespace(state, index);
-
-        bool negated = match_grapheme(state, index, '!');
-#define PAT(_tag, ...) ((pat_t){.min=min, .max=max, .negated=negated, .tag=_tag, __VA_ARGS__})
-        const char *prop_name;
-        if (match_str(state, index, ".."))
-            prop_name = "..";
-        else
-            prop_name = get_property_name(state, index);
-
-        if (!prop_name) {
-            // Literal character, e.g. {1?}
-            skip_whitespace(state, index);
-            int32_t grapheme = Text$get_grapheme_fast(state, (*index)++);
-            if (!match_grapheme(state, index, '}'))
-                fail("Missing closing '}' in pattern: ", state->stack[0].text);
-            return PAT(PAT_GRAPHEME, .grapheme=grapheme);
-        } else if (strlen(prop_name) == 1) {
-            // Single letter names: {1+ A}
-            skip_whitespace(state, index);
-            if (!match_grapheme(state, index, '}'))
-                fail("Missing closing '}' in pattern: ", state->stack[0].text);
-            return PAT(PAT_GRAPHEME, .grapheme=prop_name[0]);
-        }
-
-        skip_whitespace(state, index);
-        if (!match_grapheme(state, index, '}'))
-            fail("Missing closing '}' in pattern: ", state->stack[0].text);
-
-        switch (tolower(prop_name[0])) {
-        case '.':
-            if (prop_name[1] == '.') {
-                if (negated)
-                    return ((pat_t){.tag=PAT_END, .min=min, .max=max, .non_capturing=true});
-                else
-                    return PAT(PAT_ANY); 
-            }
-            break;
-        case 'a':
-            if (strcasecmp(prop_name, "authority") == 0) {
-                return PAT(PAT_FUNCTION, .fn=match_authority);
-            } else if (strcasecmp(prop_name, "alphanum") == 0 || strcasecmp(prop_name, "anum") == 0
-                       || strcasecmp(prop_name, "alphanumeric") == 0) {
-                return PAT(PAT_FUNCTION, .fn=match_alphanumeric);
-            }
-            break;
-        case 'c': 
-            if (strcasecmp(prop_name, "crlf") == 0)
-                return PAT(PAT_FUNCTION, .fn=match_newline);
-            break;
-        case 'd':
-            if (strcasecmp(prop_name, "digit") == 0) {
-                return PAT(PAT_PROPERTY, .property=UC_PROPERTY_DECIMAL_DIGIT);
-            }
-            break;
-        case 'e':
-            if (strcasecmp(prop_name, "end") == 0) {
-                return PAT(PAT_END, .non_capturing=!negated);
-            } else if (strcasecmp(prop_name, "email") == 0) {
-                return PAT(PAT_FUNCTION, .fn=match_email);
-            }
-#if _LIBUNISTRING_VERSION >= 0x0100000
-            else if (strcasecmp(prop_name, "emoji") == 0) {
-                return PAT(PAT_PROPERTY, .property=UC_PROPERTY_EMOJI);
-            }
-#endif
-            break;
-        case 'h':
-            if (strcasecmp(prop_name, "host") == 0) {
-                return PAT(PAT_FUNCTION, .fn=match_host);
-            }
-            break;
-        case 'i':
-            if (strcasecmp(prop_name, "id") == 0) {
-                return PAT(PAT_FUNCTION, .fn=match_id);
-            } else if (strcasecmp(prop_name, "int") == 0) {
-                return PAT(PAT_FUNCTION, .fn=match_int);
-            } else if (strcasecmp(prop_name, "ipv4") == 0) {
-                return PAT(PAT_FUNCTION, .fn=match_ipv4);
-            } else if (strcasecmp(prop_name, "ipv6") == 0) {
-                return PAT(PAT_FUNCTION, .fn=match_ipv6);
-            } else if (strcasecmp(prop_name, "ip") == 0) {
-                return PAT(PAT_FUNCTION, .fn=match_ip);
-            }
-            break;
-        case 'n':
-            if (strcasecmp(prop_name, "nl") == 0 || strcasecmp(prop_name, "newline") == 0) {
-                return PAT(PAT_FUNCTION, .fn=match_newline);
-            } else if (strcasecmp(prop_name, "num") == 0) {
-                return PAT(PAT_FUNCTION, .fn=match_num);
-            }
-            break;
-        case 's':
-            if (strcasecmp(prop_name, "start") == 0) {
-                return PAT(PAT_START, .non_capturing=!negated);
-            }
-            break;
-        case 'u':
-            if (strcasecmp(prop_name, "uri") == 0) {
-                return PAT(PAT_FUNCTION, .fn=match_uri);
-            } else if (strcasecmp(prop_name, "url") == 0) {
-                return PAT(PAT_FUNCTION, .fn=match_url);
-            }
-            break;
-        case 'w':
-            if (strcasecmp(prop_name, "word") == 0) {
-                return PAT(PAT_FUNCTION, .fn=match_id);
-            }
-            break;
-        default: break;
-        }
-
-        uc_property_t prop = uc_property_byname(prop_name);
-        if (uc_property_is_valid(prop))
-            return PAT(PAT_PROPERTY, .property=prop);
-
-        ucs4_t grapheme = unicode_name_character(prop_name);
-        if (grapheme == UNINAME_INVALID)
-            fail("Not a valid property or character name: ", prop_name);
-        return PAT(PAT_GRAPHEME, .grapheme=(int32_t)grapheme);
-#undef PAT
-    } else {
-        return (pat_t){.tag=PAT_GRAPHEME, .non_capturing=true, .min=1, .max=1, .grapheme=Text$get_grapheme_fast(state, (*index)++)};
-    }
-}
-
-static int64_t match(Text_t text, int64_t text_index, Pattern_t pattern, int64_t pattern_index, capture_t *captures, int64_t capture_index)
-{
-    if (pattern_index >= pattern.length) // End of the pattern
-        return 0;
-
-    int64_t start_index = text_index;
-    TextIter_t pattern_state = NEW_TEXT_ITER_STATE(pattern), text_state = NEW_TEXT_ITER_STATE(text);
-    pat_t pat = parse_next_pat(&pattern_state, &pattern_index);
-
-    if (pat.min == -1 && pat.max == -1) {
-        if (pat.tag == PAT_ANY && pattern_index >= pattern.length) {
-            pat.min = pat.max = MAX(1, text.length - text_index);
-        } else {
-            pat.min = 1;
-            pat.max = INT64_MAX;
-        }
-    }
-
-    int64_t capture_start = text_index;
-    int64_t count = 0, capture_len = 0, next_match_len = 0;
-
-    if (pat.tag == PAT_ANY && pattern_index >= pattern.length) {
-        int64_t remaining = text.length - text_index;
-        capture_len = remaining >= pat.min ? MIN(remaining, pat.max) : -1;
-        text_index += capture_len;
-        goto success;
-    }
-
-    if (pat.min == 0 && pattern_index < pattern.length) {
-        next_match_len = match(text, text_index, pattern, pattern_index, captures, capture_index + (pat.non_capturing ? 0 : 1));
-        if (next_match_len >= 0) {
-            capture_len = 0;
-            goto success;
-        }
-    }
-
-    while (count < pat.max) {
-        int64_t match_len = match_pat(&text_state, text_index, pat);
-        if (match_len < 0)
-            break;
-        capture_len += match_len;
-        text_index += match_len;
-        count += 1;
-
-        if (pattern_index < pattern.length) { // More stuff after this
-            if (count < pat.min)
-                next_match_len = -1;
-            else
-                next_match_len = match(text, text_index, pattern, pattern_index, captures, capture_index + (pat.non_capturing ? 0 : 1));
-        } else {
-            next_match_len = 0;
-        }
-
-        if (match_len == 0) {
-            if (next_match_len >= 0) {
-                // If we're good to go, no need to keep re-matching zero-length
-                // matches till we hit max:
-                count = pat.max;
-                break;
-            } else {
-                return -1;
-            }
-        }
-
-        if (pattern_index < pattern.length && next_match_len >= 0)
-            break; // Next guy exists and wants to stop here
-
-        if (text_index >= text.length)
-            break;
-    }
-
-    if (count < pat.min || next_match_len < 0)
-        return -1;
-
-  success:
-    if (captures && capture_index < MAX_BACKREFS && !pat.non_capturing) {
-        if (pat.tag == PAT_PAIR || pat.tag == PAT_QUOTE) {
-            assert(capture_len > 0);
-            captures[capture_index] = (capture_t){
-                .index=capture_start + 1, // Skip leading quote/paren
-                .length=capture_len - 2, // Skip open/close 
-                .occupied=true,
-                .recursive=(pat.tag == PAT_PAIR),
-            };
-        } else {
-            captures[capture_index] = (capture_t){
-                .index=capture_start,
-                .length=capture_len,
-                .occupied=true,
-                .recursive=false,
-            };
-        }
-    }
-    return (text_index - start_index) + next_match_len;
-}
-
-#undef EAT1
-#undef EAT2
-#undef EAT_MANY
-
-static int64_t _find(Text_t text, Pattern_t pattern, int64_t first, int64_t last, int64_t *match_length, capture_t *captures)
-{
-    int32_t first_grapheme = Text$get_grapheme(pattern, 0);
-    bool find_first = (first_grapheme != '{'
-                       && !uc_is_property((ucs4_t)first_grapheme, UC_PROPERTY_QUOTATION_MARK)
-                       && !uc_is_property((ucs4_t)first_grapheme, UC_PROPERTY_PAIRED_PUNCTUATION));
-
-    TextIter_t text_state = NEW_TEXT_ITER_STATE(text);
-    for (int64_t i = first; i <= last; i++) {
-        // Optimization: quickly skip ahead to first char in pattern:
-        if (find_first) {
-            while (i < text.length && Text$get_grapheme_fast(&text_state, i) != first_grapheme)
-                ++i;
-        }
-
-        int64_t m = match(text, i, pattern, 0, captures, 0);
-        if (m >= 0) {
-            if (match_length)
-                *match_length = m;
-            return i;
-        }
-    }
-    if (match_length)
-        *match_length = -1;
-    return -1;
-}
-
-public OptionalMatch_t Text$find(Text_t text, Pattern_t pattern, Int_t from_index)
-{
-    int64_t first = Int64$from_int(from_index, false);
-    if (first == 0) fail("Invalid index: 0");
-    if (first < 0) first = text.length + first + 1;
-    if (first > text.length || first < 1)
-        return NONE_MATCH;
-
-    capture_t captures[MAX_BACKREFS] = {};
-    int64_t len = 0;
-    int64_t found = _find(text, pattern, first-1, text.length-1, &len, captures);
-    if (found == -1)
-        return NONE_MATCH;
-
-    Array_t capture_array = {};
-    for (int i = 0; captures[i].occupied; i++) {
-        Text_t capture = Text$slice(text, I(captures[i].index+1), I(captures[i].index+captures[i].length));
-        Array$insert(&capture_array, &capture, I(0), sizeof(Text_t));
-    }
-    return (OptionalMatch_t){
-        .text=Text$slice(text, I(found+1), I(found+len)),
-        .index=I(found+1),
-        .captures=capture_array,
-    };
-}
-
-PUREFUNC public bool Text$has(Text_t text, Pattern_t pattern)
-{
-    if (Text$starts_with(pattern, Text("{start}"))) {
-        int64_t m = match(text, 0, pattern, 0, NULL, 0);
-        return m >= 0;
-    } else if (Text$ends_with(text, Text("{end}"))) {
-        for (int64_t i = text.length-1; i >= 0; i--) {
-            int64_t match_len = match(text, i, pattern, 0, NULL, 0);
-            if (match_len >= 0 && i + match_len == text.length)
-                return true;
-        }
-        return false;
-    } else {
-        int64_t found = _find(text, pattern, 0, text.length-1, NULL, NULL);
-        return (found >= 0);
-    }
-}
-
-public OptionalArray_t Text$matches(Text_t text, Pattern_t pattern)
-{
-    capture_t captures[MAX_BACKREFS] = {};
-    int64_t match_len = match(text, 0, pattern, 0, captures, 0);
-    if (match_len != text.length)
-        return NONE_ARRAY;
-
-    Array_t capture_array = {};
-    for (int i = 0; captures[i].occupied; i++) {
-        Text_t capture = Text$slice(text, I(captures[i].index+1), I(captures[i].index+captures[i].length));
-        Array$insert(&capture_array, &capture, I(0), sizeof(Text_t));
-    }
-    return capture_array;
-}
-
-public Array_t Text$find_all(Text_t text, Pattern_t pattern)
-{
-    if (pattern.length == 0) // special case
-        return (Array_t){.length=0};
-
-    Array_t matches = {};
-    for (int64_t i = 1; ; ) {
-        OptionalMatch_t m = Text$find(text, pattern, I(i));
-        if (!m.index.small)
-            break;
-        i = Int64$from_int(m.index, false) + m.text.length;
-        Array$insert(&matches, &m, I_small(0), sizeof(Match_t));
-    }
-    return matches;
-}
-
-typedef struct {
-    TextIter_t state;
-    Int_t i;
-    Pattern_t pattern;
-} match_iter_state_t;
-
-static OptionalMatch_t next_match(match_iter_state_t *state)
-{
-    if (Int64$from_int(state->i, false) > state->state.stack[0].text.length)
-        return NONE_MATCH;
-
-    OptionalMatch_t m = Text$find(state->state.stack[0].text, state->pattern, state->i);
-    if (m.index.small == 0) // No match
-        state->i = I(state->state.stack[0].text.length + 1);
-    else
-        state->i = Int$plus(m.index, I(MAX(1, m.text.length)));
-    return m;
-}
-
-public Closure_t Text$by_match(Text_t text, Pattern_t pattern)
-{
-    return (Closure_t){
-        .fn=(void*)next_match,
-        .userdata=new(match_iter_state_t, .state=NEW_TEXT_ITER_STATE(text), .i=I_small(1), .pattern=pattern),
-    };
-}
-
-static Text_t apply_backrefs(Text_t text, Array_t recursive_replacements, Text_t replacement, Pattern_t backref_pat, capture_t *captures)
-{
-    if (backref_pat.length == 0)
-        return replacement;
-
-    int32_t first_grapheme = Text$get_grapheme(backref_pat, 0);
-    bool find_first = (first_grapheme != '{'
-                       && !uc_is_property((ucs4_t)first_grapheme, UC_PROPERTY_QUOTATION_MARK)
-                       && !uc_is_property((ucs4_t)first_grapheme, UC_PROPERTY_PAIRED_PUNCTUATION));
-
-    Text_t ret = Text("");
-    TextIter_t replacement_state = NEW_TEXT_ITER_STATE(replacement);
-    int64_t nonmatching_pos = 0;
-    for (int64_t pos = 0; pos < replacement.length; ) {
-        // Optimization: quickly skip ahead to first char in the backref pattern:
-        if (find_first) {
-            while (pos < replacement.length && Text$get_grapheme_fast(&replacement_state, pos) != first_grapheme)
-                ++pos;
-        }
-
-        int64_t backref_len = match(replacement, pos, backref_pat, 0, NULL, 0);
-        if (backref_len < 0) {
-            pos += 1;
-            continue;
-        }
-
-        int64_t after_backref = pos + backref_len;
-        int64_t backref = parse_int(&replacement_state, &after_backref);
-        if (after_backref == pos + backref_len) { // Not actually a backref if there's no number
-            pos += 1;
-            continue;
-        }
-        if (backref < 0 || backref > 9) fail("Invalid backref index: ", backref, " (only 0-", MAX_BACKREFS-1, " are allowed)");
-        backref_len = (after_backref - pos);
-
-        if (Text$get_grapheme_fast(&replacement_state, pos + backref_len) == ';')
-            backref_len += 1; // skip optional semicolon
-
-        if (!captures[backref].occupied)
-            fail("There is no capture number ", backref, "!");
-
-        Text_t backref_text = Text$slice(text, I(captures[backref].index+1), I(captures[backref].index + captures[backref].length));
-
-        if (captures[backref].recursive && recursive_replacements.length > 0)
-            backref_text = Text$replace_array(backref_text, recursive_replacements, backref_pat, true);
-
-        if (pos > nonmatching_pos) {
-            Text_t before_slice = Text$slice(replacement, I(nonmatching_pos+1), I(pos));
-            ret = Text$concat(ret, before_slice, backref_text);
-        } else {
-            ret = Text$concat(ret, backref_text);
-        }
-
-        pos += backref_len;
-        nonmatching_pos = pos;
-    }
-    if (nonmatching_pos < replacement.length) {
-        Text_t last_slice = Text$slice(replacement, I(nonmatching_pos+1), I(replacement.length));
-        ret = Text$concat(ret, last_slice);
-    }
-    return ret;
-}
-
-public Text_t Text$replace(Text_t text, Pattern_t pattern, Text_t replacement, Pattern_t backref_pat, bool recursive)
-{
-    Text_t ret = EMPTY_TEXT;
-
-    int32_t first_grapheme = Text$get_grapheme(pattern, 0);
-    bool find_first = (first_grapheme != '{'
-                       && !uc_is_property((ucs4_t)first_grapheme, UC_PROPERTY_QUOTATION_MARK)
-                       && !uc_is_property((ucs4_t)first_grapheme, UC_PROPERTY_PAIRED_PUNCTUATION));
-
-    Text_t entries[2] = {pattern, replacement};
-    Array_t replacements = {
-        .data=entries,
-        .length=1,
-        .stride=sizeof(entries),
-    };
-
-    TextIter_t text_state = NEW_TEXT_ITER_STATE(text);
-    int64_t nonmatching_pos = 0;
-    for (int64_t pos = 0; pos < text.length; ) {
-        // Optimization: quickly skip ahead to first char in pattern:
-        if (find_first) {
-            while (pos < text.length && Text$get_grapheme_fast(&text_state, pos) != first_grapheme)
-                ++pos;
-        }
-
-        capture_t captures[MAX_BACKREFS] = {};
-        int64_t match_len = match(text, pos, pattern, 0, captures, 1);
-        if (match_len < 0) {
-            pos += 1;
-            continue;
-        }
-        captures[0] = (capture_t){
-            .index = pos, .length = match_len,
-            .occupied = true, .recursive = false,
-        };
-
-        Text_t replacement_text = apply_backrefs(text, recursive ? replacements : (Array_t){}, replacement, backref_pat, captures);
-        if (pos > nonmatching_pos) {
-            Text_t before_slice = Text$slice(text, I(nonmatching_pos+1), I(pos));
-            ret = Text$concat(ret, before_slice, replacement_text);
-        } else {
-            ret = Text$concat(ret, replacement_text);
-        }
-        nonmatching_pos = pos + match_len;
-        pos += MAX(match_len, 1);
-    }
-    if (nonmatching_pos < text.length) {
-        Text_t last_slice = Text$slice(text, I(nonmatching_pos+1), I(text.length));
-        ret = Text$concat(ret, last_slice);
-    }
-    return ret;
-}
-
-public Text_t Text$trim(Text_t text, Pattern_t pattern, bool trim_left, bool trim_right)
-{
-    int64_t first = 0, last = text.length-1;
-    if (trim_left) {
-        int64_t match_len = match(text, 0, pattern, 0, NULL, 0);
-        if (match_len > 0)
-            first = match_len;
-    }
-
-    if (trim_right) {
-        for (int64_t i = text.length-1; i >= first; i--) {
-            int64_t match_len = match(text, i, pattern, 0, NULL, 0);
-            if (match_len > 0 && i + match_len == text.length)
-                last = i-1;
-        }
-    }
-    return Text$slice(text, I(first+1), I(last+1));
-}
-
-public Text_t Text$map(Text_t text, Pattern_t pattern, Closure_t fn, bool recursive)
-{
-    Text_t ret = EMPTY_TEXT;
-
-    int32_t first_grapheme = Text$get_grapheme(pattern, 0);
-    bool find_first = (first_grapheme != '{'
-                       && !uc_is_property((ucs4_t)first_grapheme, UC_PROPERTY_QUOTATION_MARK)
-                       && !uc_is_property((ucs4_t)first_grapheme, UC_PROPERTY_PAIRED_PUNCTUATION));
-
-    TextIter_t text_state = NEW_TEXT_ITER_STATE(text);
-    int64_t nonmatching_pos = 0;
-
-    Text_t (*text_mapper)(Match_t, void*) = fn.fn;
-    for (int64_t pos = 0; pos < text.length; pos++) {
-        // Optimization: quickly skip ahead to first char in pattern:
-        if (find_first) {
-            while (pos < text.length && Text$get_grapheme_fast(&text_state, pos) != first_grapheme)
-                ++pos;
-        }
-
-        capture_t captures[MAX_BACKREFS] = {};
-        int64_t match_len = match(text, pos, pattern, 0, captures, 0);
-        if (match_len < 0) continue;
-
-        Match_t m = {
-            .text=Text$slice(text, I(pos+1), I(pos+match_len)),
-            .index=I(pos+1),
-            .captures={},
-        };
-        for (int i = 0; captures[i].occupied; i++) {
-            Text_t capture = Text$slice(text, I(captures[i].index+1), I(captures[i].index+captures[i].length));
-            if (recursive)
-                capture = Text$map(capture, pattern, fn, recursive);
-            Array$insert(&m.captures, &capture, I(0), sizeof(Text_t));
-        }
-
-        Text_t replacement = text_mapper(m, fn.userdata);
-        if (pos > nonmatching_pos) {
-            Text_t before_slice = Text$slice(text, I(nonmatching_pos+1), I(pos));
-            ret = Text$concat(ret, before_slice, replacement);
-        } else {
-            ret = Text$concat(ret, replacement);
-        }
-        nonmatching_pos = pos + match_len;
-        pos += (match_len - 1);
-    }
-    if (nonmatching_pos < text.length) {
-        Text_t last_slice = Text$slice(text, I(nonmatching_pos+1), I(text.length));
-        ret = Text$concat(ret, last_slice);
-    }
-    return ret;
-}
-
-public void Text$each(Text_t text, Pattern_t pattern, Closure_t fn, bool recursive)
-{
-    int32_t first_grapheme = Text$get_grapheme(pattern, 0);
-    bool find_first = (first_grapheme != '{'
-                       && !uc_is_property((ucs4_t)first_grapheme, UC_PROPERTY_QUOTATION_MARK)
-                       && !uc_is_property((ucs4_t)first_grapheme, UC_PROPERTY_PAIRED_PUNCTUATION));
-
-    TextIter_t text_state = NEW_TEXT_ITER_STATE(text);
-    void (*action)(Match_t, void*) = fn.fn;
-    for (int64_t pos = 0; pos < text.length; pos++) {
-        // Optimization: quickly skip ahead to first char in pattern:
-        if (find_first) {
-            while (pos < text.length && Text$get_grapheme_fast(&text_state, pos) != first_grapheme)
-                ++pos;
-        }
-
-        capture_t captures[MAX_BACKREFS] = {};
-        int64_t match_len = match(text, pos, pattern, 0, captures, 0);
-        if (match_len < 0) continue;
-
-        Match_t m = {
-            .text=Text$slice(text, I(pos+1), I(pos+match_len)),
-            .index=I(pos+1),
-            .captures={},
-        };
-        for (int i = 0; captures[i].occupied; i++) {
-            Text_t capture = Text$slice(text, I(captures[i].index+1), I(captures[i].index+captures[i].length));
-            if (recursive)
-                Text$each(capture, pattern, fn, recursive);
-            Array$insert(&m.captures, &capture, I(0), sizeof(Text_t));
-        }
-
-        action(m, fn.userdata);
-        pos += (match_len - 1);
-    }
-}
-
-Text_t Text$replace_array(Text_t text, Array_t replacements, Text_t backref_pat, bool recursive)
-{
-    if (replacements.length == 0) return text;
-
-    Text_t ret = EMPTY_TEXT;
-
-    int64_t nonmatch_pos = 0;
-    for (int64_t pos = 0; pos < text.length; ) {
-        // Find the first matching pattern at this position:
-        for (int64_t i = 0; i < replacements.length; i++) {
-            Pattern_t pattern = *(Pattern_t*)(replacements.data + i*replacements.stride);
-            capture_t captures[MAX_BACKREFS] = {};
-            int64_t len = match(text, pos, pattern, 0, captures, 1);
-            if (len < 0) continue;
-            captures[0].index = pos;
-            captures[0].length = len;
-
-            // If we skipped over some non-matching text before finding a match, insert it here:
-            if (pos > nonmatch_pos) {
-                Text_t before_slice = Text$slice(text, I(nonmatch_pos+1), I(pos));
-                ret = Text$concat(ret, before_slice);
-            }
-
-            // Concatenate the replacement:
-            Text_t replacement = *(Text_t*)(replacements.data + i*replacements.stride + sizeof(Text_t));
-            Text_t replacement_text = apply_backrefs(text, recursive ? replacements : (Array_t){}, replacement, backref_pat, captures);
-            ret = Text$concat(ret, replacement_text);
-            pos += MAX(len, 1);
-            nonmatch_pos = pos;
-            goto next_pos;
-        }
-
-        pos += 1;
-      next_pos:
-        continue;
-    }
-
-    if (nonmatch_pos <= text.length) {
-        Text_t last_slice = Text$slice(text, I(nonmatch_pos+1), I(text.length));
-        ret = Text$concat(ret, last_slice);
-    }
-    return ret;
-}
-
-public Text_t Text$replace_all(Text_t text, Table_t replacements, Text_t backref_pat, bool recursive)
-{
-    return Text$replace_array(text, replacements.entries, backref_pat, recursive);
-}
-
-public Array_t Text$split(Text_t text, Pattern_t pattern)
-{
-    if (text.length == 0) // special case
-        return (Array_t){.length=0};
-
-    if (pattern.length == 0) // special case
-        return Text$clusters(text);
-
-    Array_t chunks = {};
-
-    int64_t i = 0;
-    for (;;) {
-        int64_t len = 0;
-        int64_t found = _find(text, pattern, i, text.length-1, &len, NULL);
-        if (found == i && len == 0)
-            found = _find(text, pattern, i + 1, text.length-1, &len, NULL);
-        if (found < 0) break;
-        Text_t chunk = Text$slice(text, I(i+1), I(found));
-        Array$insert(&chunks, &chunk, I_small(0), sizeof(Text_t));
-        i = MAX(found + len, i + 1);
-    }
-
-    Text_t last_chunk = Text$slice(text, I(i+1), I(text.length));
-    Array$insert(&chunks, &last_chunk, I_small(0), sizeof(Text_t));
-
-    return chunks;
-}
-
-typedef struct {
-    TextIter_t state;
-    int64_t i;
-    Pattern_t pattern;
-} split_iter_state_t;
-
-static OptionalText_t next_split(split_iter_state_t *state)
-{
-    Text_t text = state->state.stack[0].text;
-    if (state->i >= text.length) {
-        if (state->pattern.length > 0 && state->i == text.length) { // special case
-            state->i = text.length + 1;
-            return EMPTY_TEXT;
-        }
-        return NONE_TEXT;
-    }
-
-    if (state->pattern.length == 0) { // special case
-        Text_t ret = Text$cluster(text, I(state->i+1));
-        state->i += 1;
-        return ret;
-    }
-
-    int64_t start = state->i;
-    int64_t len = 0;
-    int64_t found = _find(text, state->pattern, start, text.length-1, &len, NULL);
-
-    if (found == start && len == 0)
-        found = _find(text, state->pattern, start + 1, text.length-1, &len, NULL);
-
-    if (found >= 0) {
-        state->i = MAX(found + len, state->i + 1);
-        return Text$slice(text, I(start+1), I(found));
-    } else {
-        state->i = state->state.stack[0].text.length + 1;
-        return Text$slice(text, I(start+1), I(text.length));
-    }
-}
-
-public Closure_t Text$by_split(Text_t text, Pattern_t pattern)
-{
-    return (Closure_t){
-        .fn=(void*)next_split,
-        .userdata=new(split_iter_state_t, .state=NEW_TEXT_ITER_STATE(text), .i=0, .pattern=pattern),
-    };
-}
-
-public Pattern_t Pattern$escape_text(Text_t text)
-{
-    // TODO: optimize for spans of non-escaped text
-    Text_t ret = EMPTY_TEXT;
-    TextIter_t state = NEW_TEXT_ITER_STATE(text);
-    for (int64_t i = 0; i < text.length; i++) {
-        uint32_t g = Text$get_main_grapheme_fast(&state, i);
-        if (g == '{') {
-            ret = Text$concat(ret, Text("{1{}"));
-        } else if (g == '?'
-                   || uc_is_property_quotation_mark(g)
-                   || (uc_is_property_paired_punctuation(g) && uc_is_property_left_of_pair(g))) {
-            ret = Text$concat(ret, Text("{1"), Text$slice(text, I(i+1), I(i+1)), Text("}"));
-        } else {
-            ret = Text$concat(ret, Text$slice(text, I(i+1), I(i+1)));
-        }
-    }
-    return ret;
-}
-
-static Text_t Pattern$as_text(const void *obj, bool colorize, const TypeInfo_t *info)
-{
-    (void)info;
-    if (!obj) return Text("Pattern");
-
-    Pattern_t pat = *(Pattern_t*)obj;
-    Text_t quote = Text$has(pat, Pattern("/")) && !Text$has(pat, Pattern("|")) ? Text("|") : Text("/");
-    return Text$concat( colorize ? Text("\x1b[1m$\033[m") : Text("$"), Text$quoted(pat, colorize, quote));
-}
-
-public const TypeInfo_t Pattern$info = {
-    .size=sizeof(Pattern_t),
-    .align=__alignof__(Pattern_t),
-    .tag=TextInfo,
-    .TextInfo={.lang="Pattern"},
-    .metamethods={
-        .as_text=Pattern$as_text,
-        .hash=Text$hash,
-        .compare=Text$compare,
-        .equal=Text$equal,
-        .is_none=Text$is_none,
-        .serialize=Text$serialize,
-        .deserialize=Text$deserialize,
-    },
-};
-
-static const TypeInfo_t _text_array = {
-    .size=sizeof(Array_t),
-    .align=__alignof__(Array_t),
-    .tag=ArrayInfo,
-    .ArrayInfo.item=&Text$info,
-    .metamethods=Array$metamethods,
-};
-
-static NamedType_t _match_fields[3] = {
-    {"text", &Text$info},
-    {"index", &Int$info},
-    {"captures", &_text_array},
-};
-
-static bool Match$is_none(const void *m, const TypeInfo_t*)
-{
-    return ((OptionalMatch_t*)m)->index.small == 0;
-}
-
-public const TypeInfo_t Match$info = {
-    .size=sizeof(Match_t),
-    .align=__alignof__(Match_t),
-    .tag=StructInfo,
-    .StructInfo={
-        .name="Match",
-        .num_fields=3,
-        .fields=_match_fields,
-    },
-    .metamethods={
-        .as_text=Struct$as_text,
-        .hash=Struct$hash,
-        .compare=Struct$compare,
-        .equal=Struct$equal,
-        .is_none=Match$is_none,
-    },
-};
-
-// vim: ts=4 sw=0 et cino=L2,l1,(0,W4,m1,\:0
diff --git a/src/stdlib/patterns.h b/src/stdlib/patterns.h
deleted file mode 100644
index 2b77e490..00000000
--- a/src/stdlib/patterns.h
+++ /dev/null
@@ -1,46 +0,0 @@
-#pragma once
-
-// The type representing text patterns for pattern matching.
-
-#include <stdbool.h>
-#include <stdint.h>
-
-#include "datatypes.h"
-#include "integers.h"
-#include "optionals.h"
-#include "types.h"
-
-#define Pattern(text) ((Pattern_t)Text(text))
-#define Patterns(...) ((Pattern_t)Texts(__VA_ARGS__))
-
-typedef struct {
-    Text_t text;
-    Int_t index;
-    Array_t captures;
-} Match_t;
-
-typedef Match_t OptionalMatch_t;
-#define NONE_MATCH ((OptionalMatch_t){.index=NONE_INT})
-
-Text_t Text$replace(Text_t str, Pattern_t pat, Text_t replacement, Pattern_t backref_pat, bool recursive);
-Pattern_t Pattern$escape_text(Text_t text);
-Text_t Text$replace_all(Text_t text, Table_t replacements, Pattern_t backref_pat, bool recursive);
-Array_t Text$split(Text_t text, Pattern_t pattern);
-Closure_t Text$by_split(Text_t text, Pattern_t pattern);
-Text_t Text$trim(Text_t text, Pattern_t pattern, bool trim_left, bool trim_right);
-OptionalMatch_t Text$find(Text_t text, Pattern_t pattern, Int_t i);
-Array_t Text$find_all(Text_t text, Pattern_t pattern);
-Closure_t Text$by_match(Text_t text, Pattern_t pattern);
-PUREFUNC bool Text$has(Text_t text, Pattern_t pattern);
-OptionalArray_t Text$matches(Text_t text, Pattern_t pattern);
-Text_t Text$map(Text_t text, Pattern_t pattern, Closure_t fn, bool recursive);
-void Text$each(Text_t text, Pattern_t pattern, Closure_t fn, bool recursive);
-
-#define Pattern$hash Text$hash
-#define Pattern$compare Text$compare
-#define Pattern$equal Text$equal
-
-extern const TypeInfo_t Match$info;
-extern const TypeInfo_t Pattern$info;
-
-// vim: ts=4 sw=0 et cino=L2,l1,(0,W4,m1,\:0
diff --git a/src/stdlib/stdlib.c b/src/stdlib/stdlib.c
index fc94bc97..77383cd1 100644
--- a/src/stdlib/stdlib.c
+++ b/src/stdlib/stdlib.c
@@ -20,7 +20,6 @@
 #include "optionals.h"
 #include "metamethods.h"
 #include "nums.h"
-#include "patterns.h"
 #include "paths.h"
 #include "rng.h"
 #include "siphash.h"
diff --git a/src/stdlib/text.c b/src/stdlib/text.c
index 27acdfa4..621de942 100644
--- a/src/stdlib/text.c
+++ b/src/stdlib/text.c
@@ -998,17 +998,22 @@ PUREFUNC public int32_t Text$compare(const void *va, const void *vb, const TypeI
     return 0;
 }
 
+bool _matches(TextIter_t *text_state, TextIter_t *target_state, int64_t pos)
+{
+    for (int64_t i = 0; i < target_state->stack[0].text.length; i++) {
+        int32_t text_i = Text$get_grapheme_fast(text_state, pos + i);
+        int32_t prefix_i = Text$get_grapheme_fast(target_state, i);
+        if (text_i != prefix_i) return false;
+    }
+    return true;
+}
+
 PUREFUNC public bool Text$starts_with(Text_t text, Text_t prefix)
 {
     if (text.length < prefix.length)
         return false;
     TextIter_t text_state = NEW_TEXT_ITER_STATE(text), prefix_state = NEW_TEXT_ITER_STATE(prefix);
-    for (int64_t i = 0; i < prefix.length; i++) {
-        int32_t text_i = Text$get_grapheme_fast(&text_state, i);
-        int32_t prefix_i = Text$get_grapheme_fast(&prefix_state, i);
-        if (text_i != prefix_i) return false;
-    }
-    return true;
+    return _matches(&text_state, &prefix_state, 0);
 }
 
 PUREFUNC public bool Text$ends_with(Text_t text, Text_t suffix)
@@ -1016,12 +1021,236 @@ PUREFUNC public bool Text$ends_with(Text_t text, Text_t suffix)
     if (text.length < suffix.length)
         return false;
     TextIter_t text_state = NEW_TEXT_ITER_STATE(text), suffix_state = NEW_TEXT_ITER_STATE(suffix);
-    for (int64_t i = 0; i < suffix.length; i++) {
-        int32_t text_i = Text$get_grapheme_fast(&text_state, text.length - suffix.length + i);
-        int32_t suffix_i = Text$get_grapheme_fast(&suffix_state, i);
-        if (text_i != suffix_i) return false;
+    return _matches(&text_state, &suffix_state, text.length - suffix.length);
+}
+
+public Text_t Text$without_prefix(Text_t text, Text_t prefix)
+{
+    return Text$starts_with(text, prefix) ? Text$slice(text, I(prefix.length + 1), I(text.length)) : text;
+}
+
+public Text_t Text$without_suffix(Text_t text, Text_t suffix)
+{
+    return Text$ends_with(text, suffix) ? Text$slice(text, I(1), I(text.length - suffix.length)) : text;
+}
+
+static bool _has_grapheme(TextIter_t *text, int32_t g)
+{
+    for (int64_t t = 0; t < text->stack[0].text.length; t++) {
+        if (g == Text$get_grapheme_fast(text, t)) {
+            return true;
+        }
     }
-    return true;
+    return false;
+}
+
+public Text_t Text$trim(Text_t text, Text_t to_trim, bool left, bool right)
+{
+    int64_t first = 0;
+    TextIter_t text_state = NEW_TEXT_ITER_STATE(text), trim_state = NEW_TEXT_ITER_STATE(to_trim);
+    if (left) {
+        while (first < text.length && _has_grapheme(&trim_state, Text$get_grapheme_fast(&text_state, first))) {
+            first += 1;
+        }
+    }
+    int64_t last = text.length-1;
+    if (right) {
+        while (last >= first && _has_grapheme(&trim_state, Text$get_grapheme_fast(&text_state, last))) {
+            last -= 1;
+        }
+    }
+    return (first != 0 || last != text.length-1) ? Text$slice(text, I(first+1), I(last+1)) : text;
+}
+
+public Text_t Text$translate(Text_t text, Table_t translations)
+{
+    TextIter_t text_state = NEW_TEXT_ITER_STATE(text);
+    Text_t result = EMPTY_TEXT;
+    int64_t span_start = 0;
+    Array_t replacement_array = translations.entries;
+    for (int64_t i = 0; i < text.length; ) {
+        for (int64_t r = 0; r < replacement_array.length; r++) {
+            struct { Text_t target, replacement; } *entry = replacement_array.data + r*replacement_array.stride;
+            TextIter_t target_state = NEW_TEXT_ITER_STATE(entry->target);
+            if (_matches(&text_state, &target_state, i)) {
+                if (i > span_start)
+                    result = concat2(result, Text$slice(text, I(span_start+1), I(i)));
+
+                result = concat2(result, entry->replacement);
+                i += entry->target.length;
+                span_start = i;
+                goto found_match;
+            }
+        }
+        i += 1;
+      found_match: continue;
+    }
+    if (span_start < text.length)
+        result = concat2(result, Text$slice(text, I(span_start+1), I(text.length)));
+    return result;
+}
+
+public Text_t Text$replace(Text_t text, Text_t target, Text_t replacement)
+{
+    TextIter_t text_state = NEW_TEXT_ITER_STATE(text), target_state = NEW_TEXT_ITER_STATE(target);
+    Text_t result = EMPTY_TEXT;
+    int64_t span_start = 0;
+    for (int64_t i = 0; i < text.length; ) {
+        if (_matches(&text_state, &target_state, i)) {
+            if (i > span_start)
+                result = concat2(result, Text$slice(text, I(span_start+1), I(i)));
+
+            result = concat2(result, replacement);
+            i += target.length;
+            span_start = i;
+        } else {
+            i += 1;
+        }
+    }
+    if (span_start < text.length)
+        result = concat2(result, Text$slice(text, I(span_start+1), I(text.length)));
+    return result;
+}
+
+public bool Text$has(Text_t text, Text_t target)
+{
+    TextIter_t text_state = NEW_TEXT_ITER_STATE(text), target_state = NEW_TEXT_ITER_STATE(target);
+    for (int64_t i = 0; i < text.length; i++) {
+        if (_matches(&text_state, &target_state, i))
+            return true;
+    }
+    return false;
+}
+
+public Array_t Text$split(Text_t text, Text_t delimiters)
+{
+    if (delimiters.length == 0)
+        return Text$clusters(text);
+
+    TextIter_t text_state = NEW_TEXT_ITER_STATE(text), delim_state = NEW_TEXT_ITER_STATE(delimiters);
+    Array_t splits = {};
+    for (int64_t i = 0; i < text.length; ) {
+        int64_t span_len = 0;
+        while (i + span_len < text.length && !_matches(&text_state, &delim_state, i + span_len)) {
+            span_len += 1;
+        }
+        Text_t slice = Text$slice(text, I(i+1), I(i+span_len));
+        Array$insert(&splits, &slice, I(0), sizeof(slice));
+        i += span_len + delimiters.length;
+        if (i == text.length) {
+            Text_t empty = Text("");
+            Array$insert(&splits, &empty, I(0), sizeof(empty));
+        }
+    }
+    return splits;
+}
+
+public Array_t Text$split_any(Text_t text, Text_t delimiters)
+{
+    if (delimiters.length == 0)
+        return Array(text);
+
+    TextIter_t text_state = NEW_TEXT_ITER_STATE(text), delim_state = NEW_TEXT_ITER_STATE(delimiters);
+    Array_t splits = {};
+    for (int64_t i = 0; i < text.length; ) {
+        int64_t span_len = 0;
+        while (i + span_len < text.length && !_has_grapheme(&delim_state, Text$get_grapheme_fast(&text_state, i + span_len))) {
+            span_len += 1;
+        }
+        bool trailing_delim = i + span_len < text.length;
+        Text_t slice = Text$slice(text, I(i+1), I(i+span_len));
+        Array$insert(&splits, &slice, I(0), sizeof(slice));
+        i += span_len + 1;
+        while (i < text.length && _has_grapheme(&delim_state, Text$get_grapheme_fast(&text_state, i))) {
+            i += 1;
+        }
+        if (i >= text.length && trailing_delim) {
+            Text_t empty = Text("");
+            Array$insert(&splits, &empty, I(0), sizeof(empty));
+        }
+    }
+    return splits;
+}
+
+typedef struct {
+    TextIter_t state;
+    int64_t i;
+    Text_t delimiter;
+} split_iter_state_t;
+
+static OptionalText_t next_split(split_iter_state_t *state)
+{
+    Text_t text = state->state.stack[0].text;
+    if (state->i >= text.length) {
+        if (state->delimiter.length > 0 && state->i == text.length) { // special case
+            state->i = text.length + 1;
+            return EMPTY_TEXT;
+        }
+        return NONE_TEXT;
+    }
+
+    if (state->delimiter.length == 0) { // special case
+        state->i = text.length + 1;
+        return text;
+    }
+
+    TextIter_t delim_state = NEW_TEXT_ITER_STATE(state->delimiter);
+    int64_t i = state->i;
+    int64_t span_len = 0;
+    while (i + span_len < text.length && !_matches(&state->state, &delim_state, i + span_len)) {
+        span_len += 1;
+    }
+    Text_t slice = Text$slice(text, I(i+1), I(i+span_len));
+    state->i = i + span_len + state->delimiter.length;
+    return slice;
+}
+
+public Closure_t Text$by_split(Text_t text, Text_t delimiter)
+{
+    return (Closure_t){
+        .fn=(void*)next_split,
+        .userdata=new(split_iter_state_t, .state=NEW_TEXT_ITER_STATE(text), .i=0, .delimiter=delimiter),
+    };
+}
+
+static OptionalText_t next_split_any(split_iter_state_t *state)
+{
+    Text_t text = state->state.stack[0].text;
+    if (state->i >= text.length) {
+        if (state->delimiter.length > 0 && state->i == text.length) { // special case
+            state->i = text.length + 1;
+            return EMPTY_TEXT;
+        }
+        return NONE_TEXT;
+    }
+
+    if (state->delimiter.length == 0) { // special case
+        Text_t ret = Text$cluster(text, I(state->i+1));
+        state->i += 1;
+        return ret;
+    }
+
+    TextIter_t delim_state = NEW_TEXT_ITER_STATE(state->delimiter);
+    int64_t i = state->i;
+    int64_t span_len = 0;
+    while (i + span_len < text.length && !_has_grapheme(&delim_state, Text$get_grapheme_fast(&state->state, i + span_len))) {
+        span_len += 1;
+    }
+    Text_t slice = Text$slice(text, I(i+1), I(i+span_len));
+    i += span_len + 1;
+    while (i < text.length && _has_grapheme(&delim_state, Text$get_grapheme_fast(&state->state, i))) {
+        i += 1;
+    }
+    state->i = i;
+    return slice;
+}
+
+public Closure_t Text$by_split_any(Text_t text, Text_t delimiters)
+{
+    return (Closure_t){
+        .fn=(void*)next_split_any,
+        .userdata=new(split_iter_state_t, .state=NEW_TEXT_ITER_STATE(text), .i=0, .delimiter=delimiters),
+    };
 }
 
 PUREFUNC public bool Text$equal_values(Text_t a, Text_t b)
diff --git a/src/stdlib/text.h b/src/stdlib/text.h
index 4acca8a2..662c6e5f 100644
--- a/src/stdlib/text.h
+++ b/src/stdlib/text.h
@@ -50,6 +50,16 @@ Text_t Text$as_text(const void *text, bool colorize, const TypeInfo_t *info);
 Text_t Text$quoted(Text_t str, bool colorize, Text_t quotation_mark);
 PUREFUNC bool Text$starts_with(Text_t text, Text_t prefix);
 PUREFUNC bool Text$ends_with(Text_t text, Text_t suffix);
+Text_t Text$without_prefix(Text_t text, Text_t prefix);
+Text_t Text$without_suffix(Text_t text, Text_t suffix);
+Text_t Text$replace(Text_t text, Text_t target, Text_t replacement);
+Text_t Text$translate(Text_t text, Table_t translations);
+bool Text$has(Text_t text, Text_t target);
+Array_t Text$split(Text_t text, Text_t delimiter);
+Array_t Text$split_any(Text_t text, Text_t delimiters);
+Closure_t Text$by_split(Text_t text, Text_t delimiter);
+Closure_t Text$by_split_any(Text_t text, Text_t delimiters);
+Text_t Text$trim(Text_t text, Text_t to_trim, bool left, bool right);
 char *Text$as_c_string(Text_t text);
 __attribute__((format(printf, 1, 2)))
 public Text_t Text$format(const char *fmt, ...);
diff --git a/src/stdlib/tomo.h b/src/stdlib/tomo.h
index 4aa1253d..e42b562e 100644
--- a/src/stdlib/tomo.h
+++ b/src/stdlib/tomo.h
@@ -20,7 +20,6 @@
 #include "nums.h"
 #include "optionals.h"
 #include "paths.h"
-#include "patterns.h"
 #include "pointers.h"
 #include "print.h"
 #include "rng.h"
diff --git a/src/tomo.c b/src/tomo.c
index b91d45e0..f93dd1f8 100644
--- a/src/tomo.c
+++ b/src/tomo.c
@@ -21,7 +21,6 @@
 #include "stdlib/datatypes.h"
 #include "stdlib/integers.h"
 #include "stdlib/optionals.h"
-#include "stdlib/patterns.h"
 #include "stdlib/paths.h"
 #include "stdlib/print.h"
 #include "stdlib/text.h"
@@ -294,7 +293,12 @@ int main(int argc, char *argv[])
 
 Text_t escape_lib_name(Text_t lib_name)
 {
-    return Text$replace(lib_name, Pattern("{1+ !alphanumeric}"), Text("_"), Pattern(""), false);
+    char *libname_id = String(lib_name);
+    for (char *p = libname_id; *p; p++) {
+        if (!isalnum(*p) && *p != '_')
+            *p = '_';
+    }
+    return Text$from_str(libname_id);
 }
 
 Path_t build_file(Path_t path, const char *extension)
diff --git a/src/typecheck.c b/src/typecheck.c
index 0bfe6a07..ff609435 100644
--- a/src/typecheck.c
+++ b/src/typecheck.c
@@ -12,7 +12,6 @@
 #include "cordhelpers.h"
 #include "environment.h"
 #include "parse.h"
-#include "stdlib/patterns.h"
 #include "stdlib/paths.h"
 #include "stdlib/tables.h"
 #include "stdlib/text.h"
@@ -195,8 +194,11 @@ static env_t *load_module(env_t *env, ast_t *module_ast)
 
         env_t *module_env = fresh_scope(env);
         Table$str_set(env->imports, use->path, module_env);
-        char *libname_id = Text$as_c_string(
-            Text$replace(Text$from_str(use->path), Pattern("{1+ !alphanumeric}"), Text("_"), Pattern(""), false));
+        char *libname_id = String(use->path);
+        for (char *p = libname_id; *p; p++) {
+            if (!isalnum(*p) && *p != '_')
+                *p = '_';
+        }
         module_env->libname = libname_id;
         for (size_t i = 0; i < tm_files.gl_pathc; i++) {
             const char *filename = tm_files.gl_pathv[i];
@@ -269,6 +271,14 @@ void prebind_statement(env_t *env, ast_t *statement)
             prebind_statement(ns_env, stmt->ast);
         break;
     }
+    case Extend: {
+        auto extend = Match(statement, Extend);
+        env_t *ns_env = namespace_env(env, extend->name);
+        ns_env->libname = env->libname;
+        for (ast_list_t *stmt = extend->body ? Match(extend->body, Block)->statements : NULL; stmt; stmt = stmt->next)
+            prebind_statement(ns_env, stmt->ast);
+        break;
+    }
     default: break;
     }
 }
@@ -435,6 +445,14 @@ void bind_statement(env_t *env, ast_t *statement)
             bind_statement(ns_env, stmt->ast);
         break;
     }
+    case Extend: {
+        auto extend = Match(statement, Extend);
+        env_t *ns_env = namespace_env(env, extend->name);
+        ns_env->libname = env->libname;
+        for (ast_list_t *stmt = extend->body ? Match(extend->body, Block)->statements : NULL; stmt; stmt = stmt->next)
+            bind_statement(ns_env, stmt->ast);
+        break;
+    }
     case Use: {
         env_t *module_env = load_module(env, statement);
         if (!module_env) break;
@@ -940,7 +958,7 @@ type_t *get_type(env_t *env, ast_t *ast)
 
         // Early out if the type is knowable without any context from the block:
         switch (last->ast->tag) {
-        case UpdateAssign: case Assign: case Declare: case FunctionDef: case ConvertDef: case StructDef: case EnumDef: case LangDef:
+        case UpdateAssign: case Assign: case Declare: case FunctionDef: case ConvertDef: case StructDef: case EnumDef: case LangDef: case Extend:
             return Type(VoidType);
         default: break;
         }
@@ -1240,7 +1258,7 @@ type_t *get_type(env_t *env, ast_t *ast)
         return Type(ClosureType, Type(FunctionType, .args=args, .ret=ret));
     }
 
-    case FunctionDef: case ConvertDef: case StructDef: case EnumDef: case LangDef: {
+    case FunctionDef: case ConvertDef: case StructDef: case EnumDef: case LangDef: case Extend: {
         return Type(VoidType);
     }
 
@@ -1399,7 +1417,7 @@ PUREFUNC bool is_discardable(env_t *env, ast_t *ast)
 {
     switch (ast->tag) {
     case UpdateAssign: case Assign: case Declare: case FunctionDef: case ConvertDef: case StructDef: case EnumDef:
-    case LangDef: case Use:
+    case LangDef: case Use: case Extend:
         return true;
     default: break;
     }