JavaScript Regular Expression Parser & Visualizer.
Online : https://jex.im/regulex/
###Features:
- Written in pure JavaScript. No backend needed.
- You can embed the graph in you own site through html iframe element.
- Detailed error message. In most cases it can point out the precise syntax error position.
- No support for octal escape. Yes it is a feature. ECMAScript strict mode doesn't support octal escape in string,but many browsers still support octal escape in regex. I make things easier. In regulex, DecimalEscape will always be treated as back reference. If the back reference is invalid, e.g.
/\1/、/(\1)/、/(a)\2/,or DecimalEscape appears in charset（because in this case it can't be explained as back reference, e.g./(ab)[\1]/）, Regulex will always throw an error.
This command will generate dest/regulex.js file.
npm install requirejs -g
r.js -o build-config.jsvar parse = require('regulex').parse;
var re = /var\s+([a-zA-Z_]\w*);/ ;
console.log(parse(re.source));var parse = require('regulex').parse;
var visualize = require('regulex').visualize;
var Raphael = require('regulex').Raphael;
var re = /var\s+([a-zA-Z_]\w*);/;
var paper = Raphael('yourSvgContainer',0,0);
try {
visualize(parse(re.source),getRegexFlags(re),paper);
} catch(e) {
if (e instanceof parse.RegexSyntaxError) {
logError(re,e);
} else throw e;
}
function logError(re,err) {
var msg=["Error:"+err.message,""];
if (typeof err.lastIndex==='number') {
msg.push(re);
msg.push(new Array(err.lastIndex).join('-')+"^");
}
console.log(msg.join("\n"));
}
function getRegexFlags(re) {
var flags='';
flags+=re.ignoreCase?'i':'';
flags+=re.global?'g':'';
flags+=re.multiline?'m':'';
return flags;
}