Question

I need to try and match a string which is either a static @ or matches the pattern [^\d][\w\.\-]+.

I know I can use (...|...) to do or matches, but I can’t seem to get either @ or [^\d][\w\.\-]+ to match exclusively.

Here’s my current attempt: (@|[^\d][\w\.\-]+)

So, in this mean it would do match in the following manner:

'@'    MATCH

'www'  MATCH

'@www' NOT MATCH

'www@' NOT MATCH

'w@w'  NOT MATCH

Any suggestions?

For the record this is doing a match in PHP 5.3.

Answer 1

If you can live with a whole string match, then add ^ and $ anchors.

And the [^\d] would match anything that is not a number. Anything would include @. So add an assertion:

preg_match('/^(@|(?!@)[^\d][\w\.\-]+)$/', $subject)