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Perl: Printing hash having undefined key

+2 votes
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I want to print one hash with one key undefined . I have condition print if key exist . I guess it should not print value for undefined key, but it does .

#!/usr/bin/perl -w

@array = ("abc", 123, "dfg" ,456, "xsd",undef);
%hash = reverse @array;

foreach $k (keys %hash){
 print "key $k value $hash{$k}n" if(exists $hash{$k});
 }

And another issue is , I want to write one line code for printing hash like below:

 print "key $k value $hash{$k}n" foreach $k (keys %hash);

But it fails with error :

syntax error at my_test.pl line 16, near "$k ("
Execution of my_test.pl aborted due to compilation errors.

Please point me where am I wrong?

posted Jun 23, 2014 by anonymous

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