The Pattern-Matching Operator and $_ : Special Variables « Language Basics « Perl

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Perl » Language Basics » Special Variables

The Pattern-Matching Operator and $_


   



#By default, the pattern-matching operator examines the value stored in $_. 

#This means that you can leave out the =~ operator if you are searching $_: 



print ("hi") if ($_ =~ /abc/); 

print ("hi") if (/abc/); # these two are the same

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36.	$" is the separator
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38.	$(dollar), is the separator
39.	$MATCH = $&
40.	$SIG{__DIE__}
41.	$SIG{__WARN__} = 'IGNORE';
42.	$SIG{__WARN__} = sub {die "Warning: $_[0]"};
43.	$\ is 'END_OF_OUTPUT'
44.	$^ is the format header
45.	$^O stores the name of the operating system
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59.	List all command line argument
60.	Local builtin var
61.	Locate all numbers less than 6
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84.	The $_ Scalar Variable
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117.	foreach loop and $_
118.	or die $!
119.	or die $^E;
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127.	undef $/;

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