hello wise monks,

I'm confused about the following problem: I'm going through an excel file using Spreadsheet::XLSX. I want to print out the content of the file. There some cells which are unused, but they are not empty in terms of excel but contain a single space character or a 0(zero).

I want to omit these cells. I tried to filter the with a statement (simplified) $cell eq '' or $cell == 0 and found out that this filters out cell which contain a 'normal' strings. After further investigation I know that the problem is the '==' comparison of a string to a 0 which returns true.

I would like to have an advice if this is an intended behavior and if yes why. Here is a small piece of code to reproduce the problem:

use strict;
use warnings;


my $string = 'abcd';
my $number = 0;

if ($string == $number) {
     print "equal\n"
    }
    else {
     print "different\n" 
    }

[download]

This gives me the following output:

Argument "abcd" isn't numeric in numeric eq (==) at _eq.pl line 8.
equal

[download]

I would expect to get a 'different' printed out...

In reply to confused: string and number comparison by wwe

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