Provides (a subset of) ECMAScript regular expressions. Uses libregexp from Fabrice Bellard's QuickJS.

If you intend to use jsregexp in neovim you can place

use_rocks 'jsregexp'

in the function passed to packer.startup.

To install jsregexp globally with luarocks, run

sudo luarocks --lua-version 5.1 install jsregexp

To install jsregexp locally, run

luarocks --local --lua-version 5.1 install jsregexp

This will place the compiled module in $HOME/.luarocks/lib/lua/5.1 so $HOME/.luarocks/lib/lua/5.1/?.so needs to be added to package.cpath.

Running make in this project's root will compile the module jsregexp.so and place it in the same directory.

This module provides two functions

jsregexp.compile(regex, flags?)
jsregexp.compile_safe(regex, flags?)

that take an ECMAScript regular expression as a string and an optional string of flags:

• "i": case insensitive search
• "g": match globally
• "n": named groups
• "u": implicitly set utf-16 support if detected in the pattern string

On success, compile returns a function that takes a string as its single argument and returns a table containing all matches. On failure, compile throws an error while compile_save returns nil and an error message.

The function returns an empty table if the regular expression does not match. It will always return a table of matches even if the global flag "g" is not set and only a single match (at most) is possible.

Each match consists of a table with the fields

match.begin_ind  -- begin of the match
match.end_ind    -- end of the match, points at the last character (or byte, if non-ascii)
match.groups     -- a table containing the strings of the match group corresponding to the index

local jsregexp = require("jsregexp")

local regex, err = jsregexp.compile_safe("(\\w)\\w*", "g")
if not regex then
	print(err)
	return
end

local str = "Hello World"
local matches = regex(str)

for i, match in ipairs(matches) do
	print(string.format("match %d: %s", i, str:sub(match.begin_ind, match.end_ind)))
	if #match.groups > 0 then
		print("capture groups:")
		for j, group in ipairs(match.groups) do
			print(j, group)
		end
	end
end