you should test your regexp on ",foo," which will work, and shouldn't, as will "!!foo!!,".

So for a working single regexp you want (assuming \w is good enough)... 

/^\w+           # Starts with a "word"
 (?:,\w+)*$/x;  # Followed by many "comma and word" atoms

[download]

Which IMO is ugglier than... 

  /^[\w,]+$]/ &&  # Comma word atoms
! /^,|,,|,$/;     # With constraints on commas

[download]

It's probably faster to use 2 regexps too

--
James Antill

In reply to Re: Re: Regular Expression Question by nevyn
in thread Regular Expression Question by TASdvlper

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