ref: 0f7fbc2dcbb934a3aa62aa4a69db432b4d20b7c1
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, .opts = [ [.opt='v', .desc="dump verbose regex output"] ][:], ]) for opt : 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 : 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) | `std.Ok ln: show(re, ln, regex.exec(re, ln)) std.slfree(ln) | `std.Err `bio.Eof: break | `std.Err e: std.put("error reading from input: {}", e) break ;; ;; } /* * Renders a match in a way that's pleasant to read. There are * two cases here. * * 1) The pattern matched. In this case, we want to show the * regions of the pattern that contributed to the match. * * 2) The pattern did not match. In this case, we want to show * the location of the failed match. * * In both cases, we render a caret that describes the position * of the match. Unfortunately, for the coverage code we don't * have a great way of mapping whole subranges, so the caret can * be slightly truncated. Fixing this isn't worth hte complexity. */ 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) showpos(re, re.pcidx[re.lastip]) std.put("\t{}\n", ln) showpos(re, re.strp - 1) ;; } /* * Simple position carets for failures: Draws out * an arrow of the form: * * ~~~~~^ * * from the start of the line. */ const showpos = {re, idx std.put("\t") for var i = 0; i < idx; i++ std.put("~") ;; std.put("^\n") } /* * Coverage carets for success. This tries to output * a '^' for every section of the string that matched. * * (this|that) * ^^^^ */ 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 : hit if h std.put("^") else std.put(" ") ;; ;; std.put("\n") }