Move field access to its own file

1 files changed, 91 insertions, 0 deletions

diff --git a/src/compile/fieldaccess.c b/src/compile/fieldaccess.c
new file mode 100644
index 00000000..93b31665
--- /dev/null
+++ b/src/compile/fieldaccess.c
@@ -0,0 +1,91 @@
+// This file defines how to compile field accessing like `foo.x`
+#include "../ast.h"
+#include "../config.h"
+#include "../environment.h"
+#include "../stdlib/tables.h"
+#include "../stdlib/text.h"
+#include "../stdlib/util.h"
+#include "../typecheck.h"
+#include "declarations.h"
+#include "enums.h"
+#include "expressions.h"
+#include "pointers.h"
+#include "structs.h"
+
+Text_t compile_field_access(env_t *env, ast_t *ast) {
+    DeclareMatch(f, ast, FieldAccess);
+    type_t *fielded_t = get_type(env, f->fielded);
+    type_t *value_t = value_type(fielded_t);
+    switch (value_t->tag) {
+    case TypeInfoType: {
+        DeclareMatch(info, value_t, TypeInfoType);
+        if (f->field[0] == '_') {
+            if (!type_eq(env->current_type, info->type))
+                code_err(ast, "Fields that start with underscores are not "
+                              "accessible "
+                              "on types outside of the type definition.");
+        }
+        binding_t *b = get_binding(info->env, f->field);
+        if (!b) code_err(ast, "I couldn't find the field '", f->field, "' on this type");
+        if (b->code.length == 0) code_err(ast, "I couldn't figure out how to compile this field");
+        return b->code;
+    }
+    case TextType: {
+        const char *lang = Match(value_t, TextType)->lang;
+        if (lang && streq(f->field, "text")) {
+            Text_t text = compile_to_pointer_depth(env, f->fielded, 0, false);
+            return Texts("((Text_t)", text, ")");
+        } else if (streq(f->field, "length")) {
+            return Texts("Int$from_int64((", compile_to_pointer_depth(env, f->fielded, 0, false), ").length)");
+        }
+        code_err(ast, "There is no '", f->field, "' field on ", type_to_str(value_t), " values");
+    }
+    case StructType: {
+        return compile_struct_field_access(env, ast);
+    }
+    case EnumType: {
+        return compile_enum_field_access(env, ast);
+    }
+    case ListType: {
+        if (streq(f->field, "length"))
+            return Texts("Int$from_int64((", compile_to_pointer_depth(env, f->fielded, 0, false), ").length)");
+        code_err(ast, "There is no ", f->field, " field on lists");
+    }
+    case SetType: {
+        if (streq(f->field, "items"))
+            return Texts("LIST_COPY((", compile_to_pointer_depth(env, f->fielded, 0, false), ").entries)");
+        else if (streq(f->field, "length"))
+            return Texts("Int$from_int64((", compile_to_pointer_depth(env, f->fielded, 0, false), ").entries.length)");
+        code_err(ast, "There is no '", f->field, "' field on sets");
+    }
+    case TableType: {
+        if (streq(f->field, "length")) {
+            return Texts("Int$from_int64((", compile_to_pointer_depth(env, f->fielded, 0, false), ").entries.length)");
+        } else if (streq(f->field, "keys")) {
+            return Texts("LIST_COPY((", compile_to_pointer_depth(env, f->fielded, 0, false), ").entries)");
+        } else if (streq(f->field, "values")) {
+            DeclareMatch(table, value_t, TableType);
+            Text_t offset = Texts("offsetof(struct { ", compile_declaration(table->key_type, Text("k")), "; ",
+                                  compile_declaration(table->value_type, Text("v")), "; }, v)");
+            return Texts("({ List_t *entries = &(", compile_to_pointer_depth(env, f->fielded, 0, false),
+                         ").entries;\n"
+                         "LIST_INCREF(*entries);\n"
+                         "List_t values = *entries;\n"
+                         "values.data += ",
+                         offset,
+                         ";\n"
+                         "values; })");
+        } else if (streq(f->field, "fallback")) {
+            return Texts("({ Table_t *_fallback = (", compile_to_pointer_depth(env, f->fielded, 0, false),
+                         ").fallback; _fallback ? *_fallback : NONE_TABLE; })");
+        }
+        code_err(ast, "There is no '", f->field, "' field on tables");
+    }
+    case ModuleType: {
+        const char *name = Match(value_t, ModuleType)->name;
+        env_t *module_env = Table$str_get(*env->imports, name);
+        return compile(module_env, WrapAST(ast, Var, f->field));
+    }
+    default: code_err(ast, "Field accesses are not supported on ", type_to_str(fielded_t), " values");
+    }
+}