if condition

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

never mind, I got it... thanks anyway! \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\ so I have a foreach loop:

foreach $line (<$filelog>){
        chomp($line);
        @$ort_log[$site_index]=substr ($line, 2, 1);
        $DB::single=1;
        if ((scalar @$ort_log[$site_index])==scalar '+'){
            @$filelog[$site_index]=substr ($line, 4, -1);
            $site_index=$site_index+1;
        }else{
            @$filelog[$site_index]=(substr ($line, 4, -1))+4;
            $site_index=$site_index+1
        }
    }
[download]

in the debugger, at the breakpoint, I use

x @$ort_log[$site_index]
[download]

to check if it is + or -. The debugger says that it is -. So why does it execute the

            @$filelog[$site_index]=substr ($line, 4, -1);
            $site_index=$site_index+1;
[download]

instead of the else block? thanks

Comment on if condition Select or Download Code

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Re: if condition by jwkrahn (Abbot) on Jun 25, 2008 at 02:56 UTC
`foreach $line (<$filelog>){` Should be: `while ( my $line = <$filelog> ) {` [download] And `@$ort_log[$site_index]=substr ($line, 2, 1);` Should be: `$ort_log->[ $site_index ] = substr $line, 2, 1;` [download] And `if ((scalar @$ort_log[$site_index])==scalar '+'){ @$filelog[$site_index]=substr ($line, 4, -1); $site_index=$site_index+1; }else{ @$filelog[$site_index]=(substr ($line, 4, -1))+4; $site_index=$site_index+1 }` [download] Should be: `if ( $ort_log->[ $site_index ] eq '+'){ $filelog->[ $site_index ] = substr $line, 4, -1; $site_index++; }else{ $filelog->[ $site_index ] = substr( $line, 4, -1 ) + 4; $site_index++; }` [download]	[reply] [d/l] [select]
Re: if condition by kyle (Abbot) on Jun 25, 2008 at 03:00 UTC
Here's the condition you're talking about: `if ((scalar @$ort_log[$site_index])==scalar '+')` [download] The cause of your problem is that you're using "`==`" to compare strings, but it's only useful for comparing numbers. You need to compare with "`eq`" instead. With "`==`", you're comparing numeric values, which are both zero. Note also that `scalar '+'` is the same as `'+'`. It might also be good to write "`@$ort_log[$site_index]`" as "`${$ort_log}[$site_index]`" or "`$ort_log->[$site_index]`" to make it clear that `$ort_log` is an array reference. Your comparison would be better written: `if ( '+' eq $ort_log->[$site_index] )` [download] Hope this helps.	[reply] [d/l] [select]