Why is the following substitution of $expr (with $n_expr) in $line not working? 
print "BEFORE:LINE = $line,EXPR= $expr,NEW_EXPR= $n_expr\n";
$line =~ s/$expr/$n_expr/;
print "AFTER:LINE = $line,EXPR= $expr,NEW_EXPR= $n_expr\n";

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The o/p of above is:
BEFORE:LINE = input [`CLW:::0] abc;,EXPR = [`CLW:::0], NEW_EXPR= [$CLW
+:0]
AFTER:LINE = input [`CLW:::0] abc;,EXPR = [`CLW:::0], NEW_EXPR= [$CLW:
+0]

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The PERL-version is : V5.8.8; OS is: x86_64-linux-thread-multi

In reply to String substitution by abhay180

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