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How to read this Perl code?

Posted on 2011-03-24
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Last Modified: 2012-05-11
Hi,
What does these two lines mean?


SOME CODE

 my %validC = map { ($_ => 1) } @validC;

            return $validC{$cluster};
}

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What does this return?
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Question by:Tolgar
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wilcoxon earned 252 total points
ID: 35211350
Those lines convert the array @validC to the hash %validC (which works but good practice is to name them differently).

For instance:

@validC = (qw(jim bob ron tom))

then

%validC = (jim=>1, bob=>1, ron=>1, tom=>1)

The return will return the value of $cluster in %validC.  So, in the example if $cluster is jim, bob, ron, or tom then it will return 1 - otherwise, it will return undef.
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by:Tintin
Tintin earned 248 total points
ID: 35211358
It essentially creates a hash (%validC) and sets the value to 1 for all elements of the array @validC

The line

return $validC{$cluster};

returns what ever the value of $validC{$cluster} is.  As you don't show the code where $cluster is set, I'm guessing the value will either be 0 or 1.

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