Basic perl code

Applications Programming
1

hi,

can anybody explain me the below code. i am new to perl

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$o_dups{$1} = 1 if /^\w+\t.{19}\t([^,]+),/;

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regards,
priyanka

2

It creates hash element in %o_dups, with the key being extracted from 3rd field in TAB delimited line present in $_. The extracted part is from the start of that field to the first comma.

3 
$o_dups{$1} = 1 if /^\w+\t.{19}\t([^,]+),/;

man perlre for more info on regexes but a quick breakdown follows

$o_dups{$1}=1 # set the value in the o_dups hash for the match capture ($1) to true 
 if /^\w+\t.{19}\t([^,]+),/;#if the regex matches

The regex itself breaks down as:

/^ # beinning of line
\w+# one or more "word" characters, (ie. alphanumeric + "_")
 \t # a litteral tab
.{19} # any 19 characters
\t # a literal tab again
([^,]+) # A series of non "," chars in brackets so capture this as the first capture ($1 above)
,#followed by a comma
/ #End match