shithub: mc

ref: b0b7605bb866cccae5ea15cb9b8b18524ecc84d6
dir: /lib/regex/redump.myr/

use std
use bio
use regex

const main = {args
	var cmd, comp
	var verbose
	var fd

	verbose = false
	cmd = std.optparse(args, &[
		.argdesc = "regex [inputs...]",
		.minargs = 1,
		.maxargs = 1,
		.opts = [
			[.opt='v', .desc="dump verbose regex output"]
		][:],
	])
	for opt in cmd.opts
		match opt
		| ('v', _):	verbose = true
		| _:	std.fatal("Unknown argument")
		;;
	;;
	if verbose
		comp = regex.dbgcompile(cmd.args[0], true)
	else
		comp = regex.dbgcompile(cmd.args[0], false)
	;;
	match comp
	| `std.Err m:	
		std.fatal("unable to compile regex: {}\n", m)
	| `std.Ok re:
		if cmd.args.len > 1
			runall(re, cmd.args)
		else
			fd = bio.mkfile(0, bio.Rd)
			dump(re, fd)
			bio.close(fd)
		;;
	;;
}

const runall = {re, files

	for f in files
		match bio.open(f, bio.Rd)
		| `std.Ok fd:
			dump(re, fd)
			bio.close(fd)
		| `std.Err m:
			std.fatal("failed to open {}: {}\n", f, m)
		;;
	;;
}

const dump = {re, fd 
	while true
		match bio.readln(fd)
		| `bio.Ok ln:
			show(re, ln, regex.exec(re, ln))
			std.slfree(ln)
		| `bio.Eof:
			break
		| `bio.Err e:
			std.put("error reading from input: {}", e)
			break
		;;
	;;
}

const show = {re, ln, mg
	match mg
	| `std.Some rl:
		std.put("Matched: {}\n", rl[0])
		for var i = 1; i < rl.len; i++
			std.put("\tgroup {}: {}\n", i, rl[i])
		;;
		std.put("coverage:\n")
		std.put("\t{}\n", re.pat)
		showcoverage(re)
	| `std.None:
		std.put("Match failed at {}:\n", re.lastip)
		std.put("\t{}\n", re.pat)
		caret(re, re.pcidx[re.lastip])
		std.put("\t{}\n", ln)
		caret(re, re.strp - 1)
	;;
}

const caret = {re, idx
	std.put("\t")
	for var i = 0; i < idx; i++
		std.put("~")
	;;
	std.put("^\n")
}

const showcoverage = {re
	var hit
	var idx

	hit = std.slzalloc(re.pat.len)
	for var ip = 0; ip < re.proglen; ip++
		if !std.bshas(re.traces[re.lastthr], ip)
			continue
		;;
		idx = re.pcidx[ip]
		if idx >= 0 && idx < hit.len
			hit[idx] = true
		;;
	;;

	std.put("\t")
	for h in hit
		if h
			std.put("^")
		else
			std.put(" ")
		;;
	;;
	std.put("\n")
}