why look ahead ?= isn't working if we give pattern after it. For ex, 
if($str=~/([0-9]+)(?=welcome)to india/) {
print "Matched\n";
}

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My input string is as follows: 1welcometo india. Why it isn't getting matched? But,it gets matched when I used .* instead of "to india" after (?=welcome) in the pattern.

In reply to Look Ahead: by nvivek

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