Question

I’m trying to parse some input using regex. The input will be in the format:

{somevalue:3}

The aim is to display ‘som’ (no quotemarks).

At the moment, I have:

 'echo' => array(
            'search' => '~\{((?:'.$this->preg['var'].')(?:\.)?)\}~sU',
            'replace' => "'.\$this->_get('\\1').'"
        )

Which works great with my template system, to echo the standard variable (i.e. ‘somevalue’). However, I wish to allow the user to use the : delimiter to limit the number of characters to output (i.e. {somevalue:3} would display ‘som’).

I tried:

'echo' => array(
            'search' => '~\{((?:'.$this->preg['var'].')(?:\.)?:(.*)/)\}~sU',
            'replace' => "'.substr(\$this->_get('\\1'),0,\\2).'"
        )

But this didn’t work. I don’t really understand regex to be honest so any help would be much appreciated.

Answer 1

It looks like you have an extra ‘/’ in the new search expression.

                                                       |
                                                       v
'search' => '~\{((?:'.$this->preg['var'].')(?:\.)?:(.*)/)\}~sU',

I’m not familiar with the templating system you’re using, but it appears that the replace expression would need to be changed as well.

'replace' => "'.substr(\$this->_get('\\1'),0,\$this->_get('\\2')).'"

Put these together and you’d get something like this to try:

'echo' => array(
            'search' => '~\{((?:'.$this->preg['var'].')(?:\.)?:(.*))\}~sU',
            'replace' => "'.substr(\$this->_get('\\1'),0,\$this->_get('\\2')).'"
        )

It should be noted that if this works, the old way of doing input won’t work anymore. In other words, you’ll always have to use the format {<string>:<num_of_chars>} and not just {<string>}.