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?= in perl regex


 
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# 1  
?= in perl regex

Could anyone please make me understand how the ?= works below ..

After executing this I am getting the same output.

Code:
$string="I love chocolate.";
$string =~ s/chocolate(?= ice)/vanilla/;
print "$string\n";

# 2  
Try this Smilie

Code:
$string="I love chocolate ice.";
$string =~ s/chocolate(?= ice)/vanilla/;
print "$string\n";

# 3  
Quote:
Originally Posted by scriptscript
Could anyone please make me understand how the ?= works below ..
Code:
perldoc perlre


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