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Postings from April 2008
John W. Krahn wrote:
> Richard Lee wrote:
>>
>> something is wrong with this..
>>
>> say %yahoo's key contains the variable , X
>>
>> I wanted to go through the @array which has array of hashes... to see
>> if one of the value is equal to
>> X and if it is, wanted to assign the key of the @array to $ex_var..
>>
>> Tracing the program, it only goes through 6 lines of keys in @t_array
>> (random keys) (it has 89 keys total).. what am i doing wrong?
>>
>>
>>
>>
>> while (my ($keys,$values) = each(%yahoo) ) {
>> no strict 'refs';
>> MF: for my $i (0 .. $#t_array) {
>> for ( my($k,$v) = each(%{ $t_array[$i] } ) ) {
>
> The for loop is not doing what you appear to think it is supposed to
> be doing:
>
> $ perl -le'
> my %hash = "A" .. "Z";
> for my $c ( 1 .. 3 ) {
> my $i;
> for ( my ( $k, $v ) = each %hash ) {
> print "$c ", ++$i, qq[: \$_ = "$_" \$k = "$k" \$v = "$v"];
> }
> }
> '
> 1 1: $_ = "S" $k = "S" $v = "T"
> 1 2: $_ = "T" $k = "S" $v = "T"
> 2 1: $_ = "A" $k = "A" $v = "B"
> 2 2: $_ = "B" $k = "A" $v = "B"
> 3 1: $_ = "O" $k = "O" $v = "P"
> 3 2: $_ = "P" $k = "O" $v = "P"
>
>
> You need to use each() in a while loop instead.
>
>
>> my $keys_b = qr/$keys/;
>> if ( $v =~ m/$keys_b/ ) {
>> $ex_var = $k;
>> last MF;
>> }
>> }
>> }
>
>
> John
finally understood what you meant.. thanks!!
#!/usr/bin/perl
use warnings;
use strict;
use Data::Dumper;
my %yahoo = qw(
uno one
dos two
);
my %color = qw(
white 10
yellow 20
red 30
);
my @combine = ( \%yahoo, \%color );
print Dumper(@combine);
for my $href ( @combine ) {
while ( my ($k, $v) = each %$href ) {
#for my $keys ( keys %$href ) {
print "\$k is $k\n";
print "\$v is $v\n";
print "==========\n";
}
}
././././././ref_each.pl
$VAR1 = {
'uno' => 'one',
'dos' => 'two'
};
$VAR2 = {
'white' => '10',
'red' => '30',
'yellow' => '20'
};
$k is uno
$v is one
==========
$k is dos
$v is two
==========
$k is white
$v is 10
==========
$k is red
$v is 30
==========
$k is yellow
$v is 20
==========
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