For one thing, when you use non-standard delimiters, you need to preface them with "m". In other words, you can use /regex/ or m/regex/, or m#regex#, but you cannot use #regex# without the leading m.

Also, in perlop, you can read the following explanation as to what characters are permissible:

If "/" is the delimiter then the initial m is optional. With the m you can use any pair of non-alphanumeric, non-whitespace characters as delimiters. This is particularly useful for matching path names that contain "/", to avoid LTS (leaning toothpick syndrome). If "?" is the delimiter, then the match-only-once rule of ?PATTERN? applies. If "'" is the delimiter, no interpolation is performed on the PATTERN.

So to reiterate: In your example you're using 'a' as the delimiter. This is not allowed according to perlop. The documentation explains that the delimiter must be non-alphanumeric, and non-whitespace.


Dave

In reply to Re: Regex delimiter by davido
in thread Regex delimiter by Outaspace

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