in reply to Combining hashes

Well, this way would work... but there are others. Such as: 
my $total = scalar(keys %class1) + scalar(keys %class2) + scalar(keys 
+%class3);

#or

my $totb = 0;
$totb += $_ for map { scalar keys %$_; } (\%class1, \%class2, \%class3
+);

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As for merging, I believe the answer to be no. A hash can not have two keys of the exact same value. You can create a union of them easily enough by using 
my %new = (%class1, %class2, %class3);

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You will however lose any duplicates.

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Re: Re: Combining hashes
by MeowChow (Vicar) on May 11, 2001 at 22:08 UTC
    I believe that mpolo actually wants to lose the duplicates, since his intention is to count the total number of countries representated between employee classes.

    Also, you can rewrite: 

    my $totb = 0;
$totb += $_ for map { scalar keys %$_; } (\%class1, \%class2, \%class3
+);

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    as the following: 
    my $totb = 0;
$totb += keys %$_ for \(%class1, %class2, %class3);

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    No need to iterate twice. 
       MeowChow                                   
               s aamecha.s a..a\u$&owag.print
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[select]
      Very good point. I felt that something like that could be done to avoid the second iteration. I just gave up before I found it, thanks for showing me.
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