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PERL. Check if subroutine exists

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Last Modified: 2013-12-25
Looking for a way to find out if a named subroutine exists.

If I use the following string to invoke test.cgi:

test.cgi?act=response

and within test.cgi I have the code:

some cmd line parsing here, then
my $act=$FORM{act};
&$act;
sub response [
print "OK";
}

I want to catch a subroutine that does not exist before the default error handler gets it. Like if someone types:  test.cgi?act=resp0nSe I want to stop the script gracefully since this routine is not valid.

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ozo
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Most Valuable Expert 2014
Top Expert 2015

Commented:
Do you really want to let the user do things like
test.cgi?act=CGI::_reset_globals

it may be safer to do something like
%act=(
response => \&response,
resp0nSe => \&resp0nSe,
'CGI::_reset_globals'=>\&CGI::_reset_globals
);
&{$act{$act}||sub{print "$act does not exist\n"}};

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