BEGINning perl

By Matt S Trout (‎mst‎) from northwestengland.pm, dahut.pm, drinkers.pm, lgbt.pm
Date: Saturday, 5 December 2009 14:55
Duration: 40 minutes
Language:
Tags: begin compiler shell syntax systems

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Did you know that the original vi, when run as such, was actually effectively just ex plus -

BEGIN { run(":vi"); exit 0; }

? Well, it's amazing what you can do in perl before your program even starts. Like make it a different program, or perhaps even a different language.

Drawing on lots of tricks you've probably heard of, and quite a few you may be glad you hadn't, I'm going to show just how many things can be changed in the environment in which a program is compiled ... and why, in spite of the number of SAN checks you have to roll in the process, you just might want to do it anyway.

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Attended by: Chrsiter Lofving, Arun Prasaad (‎arunbear‎), Gordon Irving, David Dorward, Ian Wells (‎ijw‎), Paul Evans (‎LeoNerd‎), Dagfinn Ilmari Mannsåker (‎ilmari‎), fifi, Patricia Roberts (‎Pat‎), Phil Quinn, andrea rota, Marko Zagožen (‎mzagozen‎), Damon Davison (‎allolex‎), victoria conlan, Gillian Forster, Anatolie Mazur (‎Mask‎), Florian Ragwitz (‎rafl‎), Zac Stevens, Gabriele Hack (‎gabimuc‎), mirod, Andrej Fischer, Dirk De Nijs (‎ddn123456‎), Simon Elliott, Mark Rainford, Stan Sawa, Peter Flanigan,