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in reply to (tye)Re: Not Matt's Scripts
in thread Not Matt's Scripts

I've used a similar trick in the past, but rather than checking basename(), it's "unless ( caller ) { ...}", which seems to be equivalent.

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(tye)Re2: Not Matt's Scripts
by tye (Sage) on Aug 13, 2001 at 21:38 UTC

    Ah, yes. Much better! I was also thinking of an improvement to prevent the example code from sticking around when it wasn't being used. For example:

    package main; BEGIN { my $isScript= ! caller(2); sub _isScript() { $isScript } } if( _isScript ) { require CGI; my $q= CGI->new(); # ... } undef &_isScript;
    would still require that the sample code be parsed the first time that the module is used but the optimizer would know to throw the resulting code away. Not quite as pretty, though.

    Another hack to prevent even the work of parsing can be done:

    package main; unless( caller ) { my $code= do { local($/); <DATA> }; my $file= __FILE__; my $line= __LINE__ + 5; eval "\n# line $line $file\n$code; 1" or die "$@\n"; } __END__ use CGI; # ... __END__

            - tye (but my friends call me "Tye")