Question

This is javascript, but a virtually identical regex is failing in PHP too, so I don’t think it’s language specific

var r = new RegExp(     '^(:19|20)?[0-9][0-9]'            // optional 19/20 start followed by 2 numbers     + '-'                             // a hyphen     + '(:0?[1-9]|1[0-2])'             // optional 0 followed by 1-9, or 10, 11, 12     + '-'                             // a hyphen     + '(:3[01]|[12][0-9]|0?[1-9])$'   // you get the idea. ); r.test('2008-07-01');                // == false 

What on earth am I missing?

Answer 1

I think your non-capturing blocks should be e.g. (?:19|20) rather than (:19|20)