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Diffstat (limited to 'examples/patterns')
| -rw-r--r-- | examples/patterns/README.md | 444 | ||||
| -rw-r--r-- | examples/patterns/match_type.h | 8 | ||||
| -rw-r--r-- | examples/patterns/patterns.c | 1298 | ||||
| -rw-r--r-- | examples/patterns/patterns.tm | 47 |
4 files changed, 0 insertions, 1797 deletions
diff --git a/examples/patterns/README.md b/examples/patterns/README.md deleted file mode 100644 index faf2854e..00000000 --- a/examples/patterns/README.md +++ /dev/null @@ -1,444 +0,0 @@ -# Text Pattern Matching - -As an alternative to full regular expressions, Tomo provides a limited text -matching pattern syntax that is intended to solve 80% of use cases in under 1% -of the code size (PCRE's codebase is roughly 150k lines of code, and Tomo's -pattern matching code is a bit under 1k lines of code). Tomo's pattern matching -syntax is highly readable and works well for matching literal text without -getting [leaning toothpick syndrome](https://en.wikipedia.org/wiki/Leaning_toothpick_syndrome). - -For more advanced use cases, consider linking against a C library for regular -expressions or pattern matching. - -`Pat` is a [domain-specific language](docs/langs.md), in other words, it's -like a `Text`, but it has a distinct type. - -Patterns are used in a small, but very powerful API that handles many text -functions that would normally be handled by a more extensive API: - -- [`by_pattern(text:Text, pattern:Pat -> func(->PatternMatch?))`](#by_pattern) -- [`by_pattern_split(text:Text, pattern:Pat -> func(->Text?))`](#by_pattern_split) -- [`each_pattern(text:Text, pattern:Pat, fn:func(m:PatternMatch), recursive=yes)`](#each_pattern) -- [`find_patterns(text:Text, pattern:Pat -> [PatternMatch])`](#find_patterns) -- [`has_pattern(text:Text, pattern:Pat -> Bool)`](#has_pattern) -- [`map_pattern(text:Text, pattern:Pat, fn:func(m:PatternMatch -> Text), recursive=yes -> Text)`](#map_pattern) -- [`matches_pattern(text:Text, pattern:Pat -> Bool)`](#matches_pattern) -- [`pattern_captures(text:Text, pattern:Pat -> [Text]?)`](#pattern_captures) -- [`replace_pattern(text:Text, pattern:Pat, replacement:Text, backref="@", recursive=yes -> Text)`](#replace_pattern) -- [`split_pattern(text:Text, pattern:Pat -> [Text])`](#split_pattern) -- [`translate_patterns(text:Text, replacements:{Pat,Text}, backref="@", recursive=yes -> Text)`](#translate_patterns) -- [`trim_pattern(text:Text, pattern=$Pat"{space}", left=yes, right=yes -> Text)`](#trim_pattern) - -## Matches - -Pattern matching functions work with a type called `PatternMatch` that has three fields: - -- `text`: The full text of the match. -- `index`: The index in the text where the match was found. -- `captures`: A list containing the matching text of each non-literal pattern group. - -See [Text Functions](text.md#Text-Functions) for the full API documentation. - -## Syntax - -Patterns have three types of syntax: - -- `{` followed by an optional count (`n`, `n-m`, or `n+`), followed by an - optional `!` to negate the pattern, followed by an optional pattern name or - Unicode character name, followed by a required `}`. - -- Any matching pair of quotes or parentheses or braces with a `?` in the middle - (e.g. `"?"` or `(?)`). - -- Any other character is treated as a literal to be matched exactly. - -## Named Patterns - -Named patterns match certain pre-defined patterns that are commonly useful. To -use a named pattern, use the syntax `{name}`. Names are case-insensitive and -mostly ignore spaces, underscores, and dashes. - -- `..` - Any character (note that a single `.` would mean the literal period - character). -- `digit` - A unicode digit -- `email` - an email address -- `emoji` - an emoji -- `end` - the very end of the text -- `id` - A unicode identifier -- `int` - One or more digits with an optional `-` (minus sign) in front -- `ip` - an IP address (IPv4 or IPv6) -- `ipv4` - an IPv4 address -- `ipv6` - an IPv6 address -- `nl`/`newline`/`crlf` - A line break (either `\r\n` or `\n`) -- `num` - One or more digits with an optional `-` (minus sign) in front and an optional `.` and more digits after -- `start` - the very start of the text -- `uri` - a URI -- `url` - a URL (URI that specifically starts with `http://`, `https://`, `ws://`, `wss://`, or `ftp://`) -- `word` - A unicode identifier (same as `id`) - -For non-alphabetic characters, any single character is treated as matching -exactly that character. For example, `{1{}` matches exactly one `{` -character. Or, `{1.}` matches exactly one `.` character. - -Patterns can also use any Unicode property name. Some helpful ones are: - -- `hex` - Hexidecimal digits -- `lower` - Lowercase letters -- `space` - The space character -- `upper` - Uppercase letters -- `whitespace` - Whitespace characters - -Patterns may also use exact Unicode codepoint names. For example: `{1 latin -small letter A}` matches `a`. - -## Negating Patterns - -If an exclamation mark (`!`) is placed before a pattern's name, then characters -are matched only when they _don't_ match the pattern. For example, `{!alpha}` -will match all characters _except_ alphabetic ones. - -## Interpolating Text and Escaping - -To escape a character in a pattern (e.g. if you want to match the literal -character `?`), you can use the syntax `{1 ?}`. This is almost never necessary -unless you have text that looks like a Tomo text pattern and has something like -`{` or `(?)` inside it. - -However, if you're trying to do an exact match of arbitrary text values, you'll -want to have the text automatically escaped. Fortunately, Tomo's injection-safe -DSL text interpolation supports automatic text escaping. This means that if you -use text interpolation with the `$` sign to insert a text value, the value will -be automatically escaped using the `{1 ?}` rule described above: - -```tomo -# Risk of code injection (would cause an error because 'xxx' is not a valid -# pattern name: ->> user_input := get_user_input() -= "{xxx}" - -# Interpolation automatically escapes: ->> $/$user_input/ -= $/{1{}..xxx}/ - -# This is: `{ 1{ }` (one open brace) followed by the literal text "..xxx}" - -# No error: ->> some_text.find($/$user_input/) -= 0 -``` - -If you prefer, you can also use this to insert literal characters: - -```tomo ->> $/literal $"{..}"/ -= $/literal {1{}..}/ -``` - -## Repetitions - -By default, named patterns match 1 or more repetitions, but you can specify how -many repetitions you want by putting a number or range of numbers first using -`n` (exactly `n` repetitions), `n-m` (between `n` and `m` repetitions), or `n+` -(`n` or more repetitions): - -``` -{4-5 alpha} -0x{hex} -{4 digit}-{2 digit}-{2 digit} -{2+ space} -{0-1 question mark} -``` - - -# Methods - -### `by_pattern` -Returns an iterator function that yields `PatternMatch` objects for each occurrence. - -```tomo -func by_pattern(text:Text, pattern:Pat -> func(->PatternMatch?)) -``` - -- `text`: The text to search. -- `pattern`: The pattern to match. - -**Returns:** -An iterator function that yields `PatternMatch` objects one at a time. - -**Example:** -```tomo -text := "one, two, three" -for word in text.by_pattern($Pat"{id}"): - say(word.text) -``` - ---- - -### `by_pattern_split` -Returns an iterator function that yields text segments split by a pattern. - -```tomo -func by_pattern_split(text:Text, pattern:Pat -> func(->Text?)) -``` - -- `text`: The text to split. -- `pattern`: The pattern to use as a separator. - -**Returns:** -An iterator function that yields text segments. - -**Example:** -```tomo -text := "one two three" -for word in text.by_pattern_split($Pat"{whitespace}"): - say(word.text) -``` - ---- - -### `each_pattern` -Applies a function to each occurrence of a pattern in the text. - -```tomo -func each_pattern(text:Text, pattern:Pat, fn:func(m:PatternMatch), recursive=yes) -``` - -- `text`: The text to search. -- `pattern`: The pattern to match. -- `fn`: The function to apply to each match. -- `recursive`: If `yes`, applies the function recursively on modified text. - -**Example:** -```tomo -text := "one two three" -text.each_pattern($Pat"{id}", func(m:PatternMatch): - say(m.txt) -) -``` - ---- - -### `find_patterns` -Finds all occurrences of a pattern in a text and returns them as `PatternMatch` objects. - -```tomo -func find_patterns(text:Text, pattern:Pat -> [PatternMatch]) -``` - -- `text`: The text to search. -- `pattern`: The pattern to match. - -**Returns:** -A list of `PatternMatch` objects. - -**Example:** -```tomo -text := "one! two three!" ->> text.find_patterns($Pat"{id}!") -= [PatternMatch(text="one!", index=1, captures=["one"]), PatternMatch(text="three!", index=10, captures=["three"])] -``` - ---- - -### `has_pattern` -Checks whether a given pattern appears in the text. - -```tomo -func has_pattern(text:Text, pattern:Pat -> Bool) -``` - -- `text`: The text to search. -- `pattern`: The pattern to check for. - -**Returns:** -`yes` if a match is found, otherwise `no`. - -**Example:** -```tomo -text := "...okay..." ->> text.has_pattern($Pat"{id}") -= yes -``` - ---- - -### `map_pattern` -Transforms matches of a pattern using a mapping function. - -```tomo -func map_pattern(text:Text, pattern:Pat, fn:func(m:PatternMatch -> Text), recursive=yes -> Text) -``` - -- `text`: The text to modify. -- `pattern`: The pattern to match. -- `fn`: A function that transforms matches. -- `recursive`: If `yes`, applies transformations recursively. - -**Returns:** -A new text with the transformed matches. - -**Example:** -```tomo -text := "I have #apples and #oranges and #plums" -fruits := {"apples"=4, "oranges"=5} ->> text.map_pattern($Pat'#{id}', func(match:PatternMatch): - fruit := match.captures[1] - "$(fruits[fruit] or 0) $fruit" -) -= "I have 4 apples and 5 oranges and 0 plums" -``` - ---- - -### `matches_pattern` -Returns whether or not text matches a pattern completely. - -```tomo -func matches_pattern(text:Text, pattern:Pat -> Bool) -``` - -- `text`: The text to match against. -- `pattern`: The pattern to match. - -**Returns:** -`yes` if the whole text matches the pattern, otherwise `no`. - -**Example:** -```tomo ->> "Hello!!!".matches_pattern($Pat"{id}") -= no ->> "Hello".matches_pattern($Pat"{id}") -= yes -``` - ---- - -### `pattern_captures` -Returns a list of pattern captures for the given pattern. - -```tomo -func pattern_captures(text:Text, pattern:Pat -> [Text]?) -``` - -- `text`: The text to match against. -- `pattern`: The pattern to match. - -**Returns:** -An optional list of matched pattern captures. Returns `none` if the text does -not match the pattern. - -**Example:** -```tomo ->> "123 boxes".pattern_captures($Pat"{int} {id}") -= ["123", "boxes"]? ->> "xxx".pattern_captures($Pat"{int} {id}") -= none -``` - ---- - -### `replace_pattern` -Replaces occurrences of a pattern with a replacement text, supporting backreferences. - -```tomo -func replace_pattern(text:Text, pattern:Pat, replacement:Text, backref="@", recursive=yes -> Text) -``` - -- `text`: The text to modify. -- `pattern`: The pattern to match. -- `replacement`: The text to replace matches with. -- `backref`: The symbol for backreferences in the replacement. -- `recursive`: If `yes`, applies replacements recursively. - -**Returns:** -A new text with replacements applied. - -**Example:** -```tomo ->> "I have 123 apples and 456 oranges".replace_pattern($Pat"{int}", "some") -= "I have some apples and some oranges" - ->> "I have 123 apples and 456 oranges".replace_pattern($Pat"{int}", "(@1)") -= "I have (123) apples and (456) oranges" - ->> "I have 123 apples and 456 oranges".replace_pattern($Pat"{int}", "(?1)", backref="?") -= "I have (123) apples and (456) oranges" - ->> "bad(fn(), bad(notbad))".replace_pattern($Pat"bad(?)", "good(@1)") -= "good(fn(), good(notbad))" - ->> "bad(fn(), bad(notbad))".replace_pattern($Pat"bad(?)", "good(@1)", recursive=no) -= "good(fn(), bad(notbad))" -``` - ---- - -### `split_pattern` -Splits a text into segments using a pattern as the delimiter. - -```tomo -func split_pattern(text:Text, pattern:Pat -> [Text]) -``` - -- `text`: The text to split. -- `pattern`: The pattern to use as a separator. - -**Returns:** -A list of text segments. - -**Example:** -```tomo ->> "one two three".split_pattern($Pat"{whitespace}") -= ["one", "two", "three"] -``` - ---- - -### `translate_patterns` -Replaces multiple patterns using a mapping of patterns to replacement texts. - -```tomo -func translate_patterns(text:Text, replacements:{Pat,Text}, backref="@", recursive=yes -> Text) -``` - -- `text`: The text to modify. -- `replacements`: A table mapping patterns to their replacements. -- `backref`: The symbol for backreferences in replacements. -- `recursive`: If `yes`, applies replacements recursively. - -**Returns:** -A new text with all specified replacements applied. - -**Example:** -```tomo ->> text := "foo(x, baz(1))" ->> text.translate_patterns({ - $Pat"{id}(?)"="call(fn('@1'), @2)", - $Pat"{id}"="var('@1')", - $Pat"{int}"="int(@1)", -}) -= "call(fn('foo'), var('x'), call(fn('baz'), int(1)))" -``` - ---- - -### `trim_pattern` -Removes matching patterns from the beginning and/or end of a text. - -```tomo -func trim_pattern(text:Text, pattern=$Pat"{space}", left=yes, right=yes -> Text) -``` - -- `text`: The text to trim. -- `pattern`: The pattern to trim (defaults to whitespace). -- `left`: If `yes`, trims from the beginning. -- `right`: If `yes`, trims from the end. - -**Returns:** -The trimmed text. - -**Example:** -```tomo ->> "123abc456".trim_pattern($Pat"{digit}") -= "abc" -``` diff --git a/examples/patterns/match_type.h b/examples/patterns/match_type.h deleted file mode 100644 index abbc4fce..00000000 --- a/examples/patterns/match_type.h +++ /dev/null @@ -1,8 +0,0 @@ -#pragma once - -typedef struct { - Text_t text; - Int_t index; - List_t captures; -} XMatch; - diff --git a/examples/patterns/patterns.c b/examples/patterns/patterns.c deleted file mode 100644 index ee27e4e3..00000000 --- a/examples/patterns/patterns.c +++ /dev/null @@ -1,1298 +0,0 @@ -// Logic for text pattern matching - -#include <ctype.h> -#include <sys/param.h> -#include <tomo/tomo.h> -#include <unictype.h> -#include <uniname.h> -#include <unistring/version.h> - -#define MAX_BACKREFS 100 - -typedef struct { - Text_t text; - Int_t index; - List_t captures; -} PatternMatch; - -typedef struct { - Text_t text; - Int_t index; - List_t captures; - bool is_none:1; -} OptionalPatternMatch; - -#define NONE_MATCH ((OptionalPatternMatch){.is_none=true}) - -typedef struct { - int64_t index, length; - bool occupied, recursive; -} capture_t; - -typedef struct { - enum { PAT_START, PAT_END, PAT_ANY, PAT_GRAPHEME, PAT_PROPERTY, PAT_QUOTE, PAT_PAIR, PAT_FUNCTION } tag; - bool negated, non_capturing; - int64_t min, max; - union { - int32_t grapheme; - uc_property_t property; - int64_t (*fn)(TextIter_t *, int64_t); - int32_t quote_graphemes[2]; - int32_t pair_graphemes[2]; - }; -} pat_t; - -static Text_t replace_list(Text_t text, List_t replacements, Text_t backref_pat, bool recursive); - -static INLINE void skip_whitespace(TextIter_t *state, int64_t *i) -{ - while (*i < state->stack[0].text.length) { - int32_t grapheme = Text$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, Text_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, Text_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$get_grapheme_fast(&text_state, i) != first_grapheme) - ++i; - } - - int64_t m = match(text, i, pattern, 0, captures, 0); - if (m >= 0) { - if (match_length) - *match_length = m; - return i; - } - } - if (match_length) - *match_length = -1; - return -1; -} - -static OptionalPatternMatch find(Text_t text, Text_t pattern, Int_t from_index) -{ - int64_t first = Int64$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; - - List_t capture_list = {}; - for (int i = 0; captures[i].occupied; i++) { - Text_t capture = Text$slice(text, I(captures[i].index+1), I(captures[i].index+captures[i].length)); - List$insert(&capture_list, &capture, I(0), sizeof(Text_t)); - } - return (OptionalPatternMatch){ - .text=Text$slice(text, I(found+1), I(found+len)), - .index=I(found+1), - .captures=capture_list, - }; -} - -PUREFUNC static bool Pattern$has(Text_t text, Text_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); - } -} - -static bool Pattern$matches(Text_t text, Text_t pattern) -{ - capture_t captures[MAX_BACKREFS] = {}; - int64_t match_len = match(text, 0, pattern, 0, NULL, 0); - return (match_len == text.length); -} - -static OptionalList_t Pattern$captures(Text_t text, Text_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_LIST; - - List_t capture_list = {}; - for (int i = 0; captures[i].occupied; i++) { - Text_t capture = Text$slice(text, I(captures[i].index+1), I(captures[i].index+captures[i].length)); - List$insert(&capture_list, &capture, I(0), sizeof(Text_t)); - } - return capture_list; -} - -static List_t Pattern$find_all(Text_t text, Text_t pattern) -{ - if (pattern.length == 0) // special case - return (List_t){.length=0}; - - List_t matches = {}; - for (int64_t i = 1; ; ) { - OptionalPatternMatch m = find(text, pattern, I(i)); - if (m.is_none) - break; - i = Int64$from_int(m.index, false) + m.text.length; - List$insert(&matches, &m, I_small(0), sizeof(PatternMatch)); - } - return matches; -} - -typedef struct { - TextIter_t state; - Int_t i; - Text_t pattern; -} match_iter_state_t; - -static OptionalPatternMatch next_match(match_iter_state_t *state) -{ - if (Int64$from_int(state->i, false) > state->state.stack[0].text.length) - return NONE_MATCH; - - OptionalPatternMatch m = find(state->state.stack[0].text, state->pattern, state->i); - if (m.is_none) // No match - state->i = I(state->state.stack[0].text.length + 1); - else - state->i = Int$plus(m.index, I(MAX(1, m.text.length))); - return m; -} - -static Closure_t Pattern$by_match(Text_t text, Text_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, List_t recursive_replacements, Text_t replacement, Text_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 = replace_list(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$concat(ret, last_slice); - } - return ret; -} - -static Text_t Pattern$replace(Text_t text, Text_t pattern, Text_t replacement, Text_t backref_pat, bool recursive) -{ - Text_t ret = EMPTY_TEXT; - - int32_t first_grapheme = Text$get_grapheme(pattern, 0); - bool find_first = (first_grapheme != '{' - && !uc_is_property((ucs4_t)first_grapheme, UC_PROPERTY_QUOTATION_MARK) - && !uc_is_property((ucs4_t)first_grapheme, UC_PROPERTY_PAIRED_PUNCTUATION)); - - Text_t entries[2] = {pattern, replacement}; - List_t replacements = { - .data=entries, - .length=1, - .stride=sizeof(entries), - }; - - TextIter_t text_state = NEW_TEXT_ITER_STATE(text); - int64_t nonmatching_pos = 0; - for (int64_t pos = 0; pos < text.length; ) { - // Optimization: quickly skip ahead to first char in pattern: - if (find_first) { - while (pos < text.length && Text$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 : (List_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$concat(ret, last_slice); - } - return ret; -} - -static Text_t Pattern$trim(Text_t text, Text_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$slice(text, I(first+1), I(last+1)); -} - -static Text_t Pattern$map(Text_t text, Text_t pattern, Closure_t fn, bool recursive) -{ - Text_t ret = EMPTY_TEXT; - - int32_t first_grapheme = Text$get_grapheme(pattern, 0); - bool find_first = (first_grapheme != '{' - && !uc_is_property((ucs4_t)first_grapheme, UC_PROPERTY_QUOTATION_MARK) - && !uc_is_property((ucs4_t)first_grapheme, UC_PROPERTY_PAIRED_PUNCTUATION)); - - TextIter_t text_state = NEW_TEXT_ITER_STATE(text); - int64_t nonmatching_pos = 0; - - Text_t (*text_mapper)(PatternMatch, void*) = fn.fn; - for (int64_t pos = 0; pos < text.length; pos++) { - // Optimization: quickly skip ahead to first char in pattern: - if (find_first) { - while (pos < text.length && Text$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; - - PatternMatch 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 = Pattern$map(capture, pattern, fn, recursive); - List$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$concat(ret, last_slice); - } - return ret; -} - -static void Pattern$each(Text_t text, Text_t pattern, Closure_t fn, bool recursive) -{ - int32_t first_grapheme = Text$get_grapheme(pattern, 0); - bool find_first = (first_grapheme != '{' - && !uc_is_property((ucs4_t)first_grapheme, UC_PROPERTY_QUOTATION_MARK) - && !uc_is_property((ucs4_t)first_grapheme, UC_PROPERTY_PAIRED_PUNCTUATION)); - - TextIter_t text_state = NEW_TEXT_ITER_STATE(text); - void (*action)(PatternMatch, void*) = fn.fn; - for (int64_t pos = 0; pos < text.length; pos++) { - // Optimization: quickly skip ahead to first char in pattern: - if (find_first) { - while (pos < text.length && Text$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; - - PatternMatch 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) - Pattern$each(capture, pattern, fn, recursive); - List$insert(&m.captures, &capture, I(0), sizeof(Text_t)); - } - - action(m, fn.userdata); - pos += (match_len - 1); - } -} - -Text_t replace_list(Text_t text, List_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++) { - Text_t pattern = *(Text_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 : (List_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$concat(ret, last_slice); - } - return ret; -} - -static Text_t Pattern$replace_all(Text_t text, Table_t replacements, Text_t backref_pat, bool recursive) -{ - return replace_list(text, replacements.entries, backref_pat, recursive); -} - -static List_t Pattern$split(Text_t text, Text_t pattern) -{ - if (text.length == 0) // special case - return (List_t){.length=0}; - - if (pattern.length == 0) // special case - return Text$clusters(text); - - List_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$slice(text, I(i+1), I(found)); - List$insert(&chunks, &chunk, I_small(0), sizeof(Text_t)); - i = MAX(found + len, i + 1); - } - - Text_t last_chunk = Text$slice(text, I(i+1), I(text.length)); - List$insert(&chunks, &last_chunk, I_small(0), sizeof(Text_t)); - - return chunks; -} - -typedef struct { - TextIter_t state; - int64_t i; - Text_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$slice(text, I(start+1), I(text.length)); - } -} - -static Closure_t Pattern$by_split(Text_t text, Text_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), - }; -} - -static Text_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"); - - Text_t pat = *(Text_t*)obj; - Text_t quote = Pattern$has(pat, Text("/")) && !Pattern$has(pat, Text("|")) ? Text("|") : Text("/"); - return Text$concat(colorize ? Text("\x1b[1m$\033[m") : Text("$"), Text$quoted(pat, colorize, quote)); -} - -// vim: ts=4 sw=0 et cino=L2,l1,(0,W4,m1,\:0 diff --git a/examples/patterns/patterns.tm b/examples/patterns/patterns.tm deleted file mode 100644 index bab0c3dc..00000000 --- a/examples/patterns/patterns.tm +++ /dev/null @@ -1,47 +0,0 @@ -use ./patterns.c - -struct PatternMatch(text:Text, index:Int, captures:[Text]) - -lang Pat - convert(text:Text -> Pat) - return C_code:Pat(Pattern$escape_text(@text)) - - convert(n:Int -> Pat) - return Pat.from_text("$n") - -extend Text - func matches_pattern(text:Text, pattern:Pat -> Bool) - return C_code:Bool(Pattern$matches(@text, @pattern)) - - func pattern_captures(text:Text, pattern:Pat -> [Text]?) - return C_code:[Text]?(Pattern$captures(@text, @pattern)) - - func replace_pattern(text:Text, pattern:Pat, replacement:Text, backref="@", recursive=yes -> Text) - return C_code:Text(Pattern$replace(@text, @pattern, @replacement, @backref, @recursive)) - - func translate_patterns(text:Text, replacements:{Pat=Text}, backref="@", recursive=yes -> Text) - return C_code:Text(Pattern$replace_all(@text, @replacements, @backref, @recursive)) - - func has_pattern(text:Text, pattern:Pat -> Bool) - return C_code:Bool(Pattern$has(@text, @pattern)) - - func find_patterns(text:Text, pattern:Pat -> [PatternMatch]) - return C_code:[PatternMatch](Pattern$find_all(@text, @pattern)) - - func by_pattern(text:Text, pattern:Pat -> func(->PatternMatch?)) - return C_code:func(->PatternMatch?)(Pattern$by_match(@text, @pattern)) - - func each_pattern(text:Text, pattern:Pat, fn:func(m:PatternMatch), recursive=yes) - C_code { Pattern$each(@text, @pattern, @fn, @recursive); } - - func map_pattern(text:Text, pattern:Pat, fn:func(m:PatternMatch -> Text), recursive=yes -> Text) - return C_code:Text(Pattern$map(@text, @pattern, @fn, @recursive)) - - func split_pattern(text:Text, pattern:Pat -> [Text]) - return C_code:[Text](Pattern$split(@text, @pattern)) - - func by_pattern_split(text:Text, pattern:Pat -> func(->Text?)) - return C_code:func(->Text?)(Pattern$by_split(@text, @pattern)) - - func trim_pattern(text:Text, pattern=$Pat"{space}", left=yes, right=yes -> Text) - return C_code:Text(Pattern$trim(@text, @pattern, @left, @right)) |