Optimizing code

This is a page on code optimization--practices that encourage efficient code.

Avoid shift

The shift() function, used to get the first variable from arrays like the @_ argument list for functions, is slow. Use these alternatives instead:

• For short functions (1-5 lines), use $_[0] for the first argument, $_[1] for the second, etc.
• For longer functions, use the following construct to assign the values to named scalars:

my ( $foo, $bar ) = @_;

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