benbon / lua-regex

regular expression for lua

lua-regex

regular expression for lua.

NOTE: this module is under heavy development.

Dependencies

• lua-pcre2: https://github.com/mah0x211/lua-pcre2

---

regex module

local regex = require('regex')

Regular expression flags

• i: Do caseless matching.
• s: . matches anything including NL.
• m: ^ and $ match newlines within data.
• u: Treat pattern and subjects as UTF strings.
• U: Do not check the pattern for UTF valid.
• x: Ignore white space and # comments.
• o: compile-once mode that caching a compiled regex.
• g: global match.
• j: enable JIT compilation.

Creating a Regex object

re, err = regex.new( pattern [, flgs] )

creates a new regex object.

Params

• pattern:string: string containing expression to be compiled.
• flgs:string: regular expression flags.

Returns

• re:table: regex object.
• err:string: error message.

Instance Methods

arr, err = re:match( sbj [, offset] )

matches a compiled regular expression against a given subject string. It returns matched substrings.

Params

• sbj:string: the subject string.
• offset:number: offset in the subject at which to start matching.

Returns

• arr:table: array of matched substrings.
• err:string: error message.

arr, err = re:matches( sbj [, offset] )

almost same as match method but it returns all matched substrings except capture strings.

Params

• sbj:string: the subject string.
• offset:number: offset in the subject at which to start matching.

Returns

• arr:table: array of matched substrings.
• err:string: error message.

heads, tails, err = re:indexof( sbj [, offset] )

almost same as match method but it returns offsets of matched substrings.

Params

• sbj:string: the subject string.
• offset:number: offset in the subject at which to start matching.

Returns

• heads:table: array of head offset of matched substrings.
• tails:table: array of tail offset of matched substrings.
• err:string: error message.

heads, tails, err = re:indexesof( sbj [, offset] )

almost same as match method but it returns all offsets of matched substrings except capture strings.

Params

• sbj:string: the subject string.
• offset:number: offset in the subject at which to start matching.

Returns

• heads:table: array of head offset of matched substrings.
• tails:table: array of tail offset of matched substrings.
• err:string: error message.

ok, err = re:test( sbj [, offset] )

returns true if there is a matched.

Params

• sbj:string: the subject string.
• offset:number: offset in the subject at which to start matching.

Returns

• ok:boolean: true on matched.
• err:string: error message.

Static Methods

arr, err = regex.match( sbj, pattern [, flgs [, offset]] )

same as match instance method.

Params

• sbj:string: the subject string.
• pattern:string: string containing expression to be compiled.
• flgs:string: regular expression flags.
• offset:number: offset in the subject at which to start matching.

Returns

• arr:table: array of matched substrings.
• err:string: error message.

arr, err = regex.matches( sbj, pattern [, flgs [, offset]] )

same as matches instance method.

Params

• sbj:string: the subject string.
• pattern:string: string containing expression to be compiled.
• flgs:string: regular expression flags.
• offset:number: offset in the subject at which to start matching.

Returns

• arr:table: array of matched substrings.
• err:string: error message.

heads, tails, err = regex.indexof( sbj, pattern [, flgs [, offset]] )

same as indexof instance method.

Params

• sbj:string: the subject string.
• pattern:string: string containing expression to be compiled.
• flgs:string: regular expression flags.
• offset:number: offset in the subject at which to start matching.

Returns

• heads:table: array of head offset of matched substrings.
• tails:table: array of tail offset of matched substrings.
• err:string: error message.

heads, tails, err = regex.indexesof( sbj, pattern [, flgs [, offset]] )

same as indexesof instance method.

Params

• sbj:string: the subject string.
• pattern:string: string containing expression to be compiled.
• flgs:string: regular expression flags.
• offset:number: offset in the subject at which to start matching.

Returns

• heads:table: array of head offset of matched substrings.
• tails:table: array of tail offset of matched substrings.
• err:string: error message.

ok, err = regex.test( sbj, pattern [, flgs [, offset]] )

same as test instance method.

Params

• sbj:string: the subject string.
• pattern:string: string containing expression to be compiled.
• flgs:string: regular expression flags.
• offset:number: offset in the subject at which to start matching.

Returns

• ok:boolean: true on matched.
• err:string: error message.