Links convertation

Question

I have made this links converting function that puts url in <a></a>tags:

function convert_links($text) {
    $text = explode(' ',$text);
    for($i=0;$i<count($text);$i++) {
        if(filter_var($text[$i], FILTER_VALIDATE_URL))
            $text[$i] = "<a href='".$text[$i]."' target='_blank'>".$text[$i]."</a>";
        else 
            $text[$i] = $text[$i];
    }
    return implode(' ',$text);
}

I am newbie in optimization, so I want to ask: can I make this function work better/ faster? I heard that array_filter is better choice in this situation, however I can not make it work. Thanks for your help!

Now I have made one more function with array_map. so, which one is better to use?

function convert_links($text) {
    $text = explode(' ', $text);
    function convert_link($val) {
        if(filter_var($val,FILTER_VALIDATE_URL))
            return "<a href='".$val."' target='_blank'>".$val."</a>";
        else
            return $val;
    }
    $text = array_map('convert_link',$text);
    return implode(' ',$text);
}

Danielius

We help fix broken code. code optimization is basically offtopic. — Marc B, Jul 19 '16 at 17:43
oh, sorry about that then, should i remove my question? :) just have seen that tag "optimization" exists — Danielius, Jul 19 '16 at 17:44
Post your code with "array_filter", let's see why you cannot make it work (click "edit" under your question, paste the code with array_filter, save the question). — Jose Manuel Abarca Rodríguez, Jul 19 '16 at 17:52
`array_filter` does not seem like a good choice for this. `array_map` would make more sense. — Don't Panic, Jul 19 '16 at 17:55
I have made new function now, sorry, about that array_filter. So, which one is better? :) — Danielius, Jul 19 '16 at 18:11
http://stackoverflow.com/questions/1200214/how-can-i-measure-the-speed-of-code-written-in-php — Jose Manuel Abarca Rodríguez, Jul 19 '16 at 18:26

trincot · Accepted Answer · 2016-07-19T19:15:11.813

1

As an alternative you could use preg_replace_callback:

function convert_links($text) {
    return preg_replace_callback("/\S+:\S+/", function ($match) {
        return filter_var($val = $match[0], FILTER_VALIDATE_URL)
            ? "<a href='$val' target='_blank'>$val</a>"
            : $val;
    }, $text);
}

Note that:

Instead of an if with two return statements, you can have one return and the ternary operator ? ... :.
In double quoted strings you can just embed your variable; no need to concatenate with ..
This function also works if URLs are separated by other white space than space (like newline, tab, ...).
The regular expression requires the word to contain at least one : not at the start or end of the word. This will avoid the more expensive filter_var calls being made on "normal" words.

edited Jul 19 '16 at 19:15

answered Jul 19 '16 at 19:03

trincot

317,000
35
244
286

But I tried once and now know that `"$variable"` works slower than `".$variable."`, so i will change it :) – Danielius Jul 20 '16 at 07:34
You're welcome. That is an interesting observation about `"$variable"`! – trincot Jul 20 '16 at 07:47
http://stackoverflow.com/a/4871172/4402190 here I read such info :) Interesting stuff! – Danielius Jul 20 '16 at 08:00

Links convertation

1 Answers1