Dear Monks

While thinking everything should be working fine, I got the following problem, demonstrated by the code below:
#! /usr/bin/perl -lw
use strict ;


my %r = ( 'a' => 1, 'b' => 2, 'c' => 3) ;

my $keys = keys(%r) ;
print "keys = $keys" ;

printf "keys=%d\n", keys(%r) ;

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Output
keys = 3
Argument "c" isn't numeric in printf at ./t12.pl line 12.
keys=0

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So, the second time keys(%r) is not used in scalar context. I tried everything I could think of to get it into scalar context, but only 
printf "keys=%d\n", (my $sc = keys(%r)) ;

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seems to work, which doesn't look like the best solution :)
Any suggestions ?

Thnx
LuCa

In reply to keys(%hash) not in scalar context in printf by jeanluca

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