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Using 0 (zero) as a Value?

Jan 9, 2004, 11:34 AM

Watts

Veteran (1141 posts)

Jan 9, 2004, 11:34 AM

Post #1 of 2

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Using 0 (zero) as a Value?

I set up a configuration file (example)

#do something
#(1=yes do something, 0=no don't)
#---------------------------------------
$varSomething = "0";

if ($varSomething) {big fun}
else {no fun at all}

Now, when I run this script it gives an error when the value is set to "0".

"...file did not return a true value at line blah"

Of course, I thought that was the whole point of 1 or 0. Any pointers?

In the mean time I simply changed the instructions to use 1=yes and 2=no and then used
if ($varSomething == "1") { } else { }

Any help is much appreciated...

Also, how do I do a "timer" for input? I have $inPut = <STDIN>; (and then what to do if yes or no, etc) but I'd like someway to kill the program if no input for 60 seconds or so.

Jan 9, 2004, 12:26 PM

Andy

Veteran / Moderator (18441 posts)

Jan 9, 2004, 12:26 PM

Post #2 of 2

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Re: [Watts] Using 0 (zero) as a Value? In reply to

This should work;

Code:
#!/usr/bin/perl 

use CGI; 
my $IN = new CGI; 

print $IN->header(); 

my $var = 1; 

if ($var) {  
    print "First one was true...<BR>";  
} else {  
    print "First one was false...<BR>";   
} 

my $var2 = 0; 

if ($var2) {  
    print "Second one was true...<BR>";  
} else {  
    print "Second one was false...<BR>";   
} 

my $var3 = "0"; 

if ($var3) {  
    print "Third one was true...<BR>";  
} else {  
    print "Third one was false...<BR>";   
}

Untested, but that should give;

Quote:

First one was true...
Second one was false...
Third one was false...

Cheers

Andy (mod)
andy@ultranerds.co.uk

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