Grep in PERL


 
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# 1  
Old 09-18-2012
Grep in PERL

Hi,

Can anybody let me know how this grep will work.
The input and output is not known.

Quote:
my @unique = grep { ! $seen{ $_ }++ } @$in
Also can you give me the details of any link where i can find clearly about grep
Thanks in advance
# 2  
Old 09-18-2012
Quote:
Originally Posted by irudayaraj
Can anybody let me know how this grep will work.
The input and output is not known.

Code:
my @unique = grep { ! $seen{ $_ }++ } @$in

Value referred by $seen{$_} is incremented, and the elements from @in that doesn't contain new $seen{$_} is picked and stored in @unique.

Quote:
Also can you give me the details of any link where i can find clearly about grep
Read about grep in perldoc.
This User Gave Thanks to balajesuri For This Post:
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