Perl would gain a big leap in flexibility if a pragma (or whatever) could state something like: "use LessMem;"

The perl porters are aware of this, as the documentation for the less pragma shows:

NAME
       less - perl pragma to request less of something from the
       compiler

SYNOPSIS
           use less;  # unimplemented

DESCRIPTION
       Currently unimplemented, this may someday be a compiler
       directive to make certain trade-offs, such as perhaps

           use less 'memory';
           use less 'CPU';
           use less 'fat';
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Ofcourse, as it is unimplemented, it is still useless in practice, but you could try convincing the perl 5 porters that it should at least do something in 5.10.

-- 
Joost       downtime n. The period during which a system
            is error-free and immune from user input.
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