how can i check an array element as empty or not

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

Hi monks, my code is

print  "usage_grpinf[2] :$usage_grpinf[2]\n";
if ( $usage_grpinf[2] eq "")
{
print "event_date valid2\n";
}

output is
-- Call_UsingHash12.pl
usage_grpinf[2] :
[download]

Actually the element is empty but message "event_date valid2" is not getting printed. can any body help me in this?

Comment on how can i check an array element as empty or not Download Code

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Re: how can i check an array element as empty or not by susanti13 (Novice) on Jul 21, 2009 at 06:06 UTC
$usage_grpinf[2] may be undefined or contains spaces/characters. add "use strict" or/and "use warnings". If $usage_grpinf[2]is undefined, it will give such warnings when you execute the program. also try printing $usage_grpinf[2] enclosed in brackets so you'll know if it contains spaces or newlines i.e. print "usage_grpinf[2] : \|$usage_grpinf[2]\|\n";	[reply]
Re^2: how can i check an array element as empty or not by Anonymous Monk on Jul 21, 2009 at 07:27 UTC
you could also `C:\>perl -le print(chr(9)) \|cat -v ^M C:\>perl -le print(chr(9)) \|od -tax1 0000000 ht cr nl 09 0d 0a 0000003 C:\>perl -le print(chr(9)) \|hexdump 00000000: 09 0D 0A - \| \| 00000003;` [download]	[reply] [d/l]
Re^2: how can i check an array element as empty or not by Anonymous Monk on Jul 21, 2009 at 06:21 UTC
Thanks all, It had a tab as the element :)	[reply]
Re: how can i check an array element as empty or not by ikegami (Patriarch) on Jul 21, 2009 at 05:41 UTC
Then perhaps it only appears empty (e.g. it contains a space or a newline).	[reply]