While your example works as shown it is contrary to the docs (perlop) and also fails to explain the observed behaviour noted above..... 

If ``/'' is the delimiter then the initial m is optional. With the m y
+ou can use any pair of non-alphanumeric, non-whitespace characters as
+ delimiters.

C:\>type test.pl
$re =~ "^0\$";
$re =~ m"^0\$";
$re =~ '^0\$';
$re =~ m'^0\$';
$re =~ <^0\$>;
$re =~ m<^0\$>;

C:\>perl -MO=Deparse test.pl
$re =~ /^0$/;
$re =~ /^0\$/;
$re =~ /^0\$/;
$re =~ /^0\$/;
$re =~ /CORE::GLOBAL::glob('^0$', 0)/;
$re =~ /^0\$/;
test.pl syntax OK
C:\>

[download]

The quote and other chars can also be used without m but the results may not be intuitive.....

cheers

tachyon

In reply to Re: Re: Re: what function of this Regular Expression? by tachyon
in thread what function of this Regular Expression? by iwanthome

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