add PHP preg_replace_callback()

[Peter]

Hi, at Contributing is not clear who to do a simple contribution with a new function... Need to fork or can be here?

Description

We can copy/paste or adapt from FGRibreau the PHP's preg_replace_callback()

function preg_replace_callback(pattern, callback, subject, limit){
    // Perform a regular expression search and replace using a callback
    // 
    // discuss at: http://geekfg.net/
    // +   original by: Francois-Guillaume Ribreau (http://fgribreau)
    // *     example 1: preg_replace_callback("/(\\@[^\\s,\\.]*)/ig",function(matches){return matches[0].toLowerCase();},'#FollowFriday @FGRibreau @GeekFG',1);
    // *     returns 1: "#FollowFriday @fgribreau @GeekFG"
    // *     example 2: preg_replace_callback("/(\\@[^\\s,\\.]*)/ig",function(matches){return matches[0].toLowerCase();},'#FollowFriday @FGRibreau @GeekFG');
    // *     returns 2: "#FollowFriday @fgribreau @geekfg"
    limit = !limit?-1:limit;
    var _flag = pattern.substr(pattern.lastIndexOf(pattern[0])+1),
        _pattern = pattern.substr(1,pattern.lastIndexOf(pattern[0])-1),
        reg = new RegExp(_pattern,_flag),
        rs = null,
        res = [],
        x = 0,
        ret = subject;

    if (limit === -1){
        var tmp = [];
        do{
            tmp = reg.exec(subject);
            if(tmp !== null){
                res.push(tmp);
            }
        }while(tmp !== null && _flag.indexOf('g') !== -1)
    } else
        res.push(reg.exec(subject));
    for(x = res.length-1; x > -1; x--)
        ret = ret.replace(res[x][0],callback(res[x]));
    return ret;
}

PS: adapt option is preg_replace_callback(reg,callback, subject, limit).

[Kevin van Zonneveld]

Hi @ppKrauss, thanks! I checked https://github.com/kvz/locutus/blob/master/CONTRIBUTING.md but it seems it does mention about PRs?

However for this function, we won't be merging it in I'm afraid for two reasons:

a) It does not comply with our coding convention, but even if it was made to adhere to that:
b) It cannot offer compatible behavior with PHP as it has a different regex engine, so there will be a ton of subtle differences, that will each result in a github issue if people start using this and assume it works the same as the PHP version.

Probably not the answer you were hoping for, I'm sorry about that!