Wrap first word in tag with preg_replace -- can't reference fullstring match

Question

I generated the following regex code with http://gskinner.com/RegExr/ where it works, but when I execute it with PHP, it fails to use the match in the replacement string. ``` preg_replace( '/(?<=\>)\b\w*\b|^\w*\b/', '$&', 'an example' ); ``` Output: ``` $& example ``` Expected: ``` an example ``` I know that obviously the `$&` is not doing the correct thing, but how can I get it to work?

Accepted Answer

Try with this instead ``` preg_replace('/(?<=\>)\b\w*\b|^\w*\b/', '$0', $string); ``` $0 means it will become the first thing matched in your regex, $1 will become the second etc. You could also use back-references; \0 gets the first thing matched back from where you are, \1 gets the second thing matched back etc. More Info

Wrap first word in <b> tag with preg_replace -- can't reference fullstring match

Solution

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