size of an array of hash

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

dear monks,
i have a problem while retrieving the size of an array of hash passed as an argument of a sub.
Please consider the following code.

#!/usr/bin/perl -w

use strict;
sub rien2rien (@)
{
    my @other = shift;
    for (my $i = 0; $i < @other; $i++)
    {
        my $a = $other[$i]{'first'};
        my $b = $other[$i]{'second'};
        print "in other sub:\t$a\t$b\n";
    }
}

sub rien ()
{
    my $i = 0;
    my $file ="somefile.html";
    my $regexp = "(.*)something(.*)";
    open(FH, "<$file");

    my @rrayOfHash;
    (my @data) = split(/<br>/, <FH>);
    foreach my $tuff (@data)
    {
    if ($tuff =~ /$regexp/)
     {
            $rrayOfHash[$i]{'first'} = $1;
            $rrayOfHash[$i]{'second'} =$2;
             $i++;
        }
    }
    for ($i = 0 ;$i <@data; $i++)
    {
        my $a = $rrayOfHash[$i]{'first'};
        my $b = $rrayOfHash[$i]{'second'};
        print "in sub: \t$a\t$b\n";
    }
    return @rrayOfHash;
}

my @ut = &rien();
for (my $i = 0; $i < @ut; $i++)
{
        my $a = $ut[$i]{'first'};
        my $b = $ut[$i]{'second'};
        print "in main:\t$a\t$b\n";
 }
&rien2rien(@ut);
[download]

the code produce this output :

in sub:         bla      bleu 
in sub:         bli      blo
in main:        bla      bleu 
in main:        bli      blo
in other sub:   bla      bleu
[download]

i imagine it may be a context question but i can't manage how to retrieve the whole array in the "other sub".

Thanks in advance for your help

Comment on size of an array of hash Select or Download Code

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Re: size of an array of hash by ikegami (Patriarch) on Oct 04, 2005 at 01:16 UTC
GrandFather showed you how to pass the array. However, it would be more efficient if a reference to the array was passed: `&rien2rien(\@ut); . . . sub rien2rien { my $other = shift; for (my $i = 0; $i < @$other; $i++) { my $a = $other->[$i]{'first'}; my $b = $other->[$i]{'second'}; print "in other sub:\t$a\t$b\n"; } }` [download] Other problems: 1) $a and $b have special meanings for `sort`. Using them as normal variables can cause unexpected problems. Use other names instead. 2) You're using prototypes (e.g. `sub rien2rien``(@)`), which is a bad idea. 3) You use the ampersand notation for calling functions (e.g. `&``rien2rien(@ut)` ) which overrides the prototype, also a bad idea. 4) You're using a C-style for loop, which is much less readable and no more efficient than a Perl-style for loop, or even a foreach loop: `sub rien2rien { my $other = shift; foreach (@$other) { my $var1 = $_->{'first'}; my $var2 = $_->{'second'}; print "in other sub:\t$var1\t$var2\n"; } }` [download]	[reply] [d/l] [select]
Re: size of an array of hash by GrandFather (Saint) on Oct 04, 2005 at 00:08 UTC
If you change `my @other = shift;` (which simply copies the first parameter to the sub into @other) to `my @other = (@_);` which generates an array containing all the parameters passed in and assigns that to @other. Using the line "firstsomethingsecond nextsomethinganother " as the data the test code generates: `in sub: first second in sub: next another in main: first second in main: next another in main: in other sub: first second in other sub: next another in other sub:` [download] Perl is Huffman encoded by design.	[reply] [d/l] [select]
Re: size of an array of hash by GrandFather (Saint) on Oct 03, 2005 at 23:37 UTC
I suggest you change the `<FH>` to a `<DATA>`, comment out the `open` line, and provide some sample data for test purposes. Perl is Huffman encoded by design.	[reply] [d/l] [select]