So what your saying is that because someone might do

print ${exists $foo{'bar'};

instead of

print $$_ if $_ = exists $foo{'bar'};

and get a runtime error something like Use of uninitialized value in scalar dereference ...

you would prevent anyone from benefiting from the advantages of using it properly?

Given that in the example above, the user has at least acknowledge that $foo{'bar'} may not exist by the very act of using exists, then that's seems analogous to, and a much less easy mistake to make than doing

print $foo{'bar'};

instead of

print $foo{'bar'} if exists $foo{'bar'}

currently, which also results in a runtime warning.

Isn't it kind of against the spirit of Perl's we ask you to read the warning signs rather than enforce them with a shotgun approach?


Examine what is said, not who speaks.

The 7th Rule of perl club is -- pearl clubs are easily damaged. Use a diamond club instead.


In reply to Re: Re: optimization - exists should return a reference by BrowserUk
in thread optimization - exists should return a reference by John M. Dlugosz

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