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Re: Smartmatch two cents (was... List::Util... when...)

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From:
Ed Avis
Date:
July 3, 2012 01:59
Subject:
Re: Smartmatch two cents (was... List::Util... when...)
Message ID:
loom.20120703T104914-103@post.gmane.org
Just a couple more thoughts on the suggestion of an 'in' operator
(which others besides me have proposed).

The current convention is that punctuation operators like == != < are
numeric, while alphabetic ones like eq ne lt do string comparisons.
An 'in' operator doing string comparison follows that convention.
While you could also have an equivalent in== operator, in my
experience that operation is much less common than the string version.

As in Python, 'in' could work for both arrays and hashes:

   $x in @array

   $x in %hash    # same as exists $hash{$x}

With the auto-dereferencing introduced in recent perls, the RHS could
be an array or hash ref.

   $x in $hash_ref    # same as exists $hash_ref->{$x}

I do not envisage the 'in' operator being part of some grand scheme
which will replace all functionality provided by smartmatch, but just
propose it as a simple operator which is useful in its own right and,
in my opinion, can make for clearer and more concise code.

--
Ed Avis <eda@waniasset.com>


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