If you hate "magic numbers" appearing scattered throughout a script, you can use enum to set up constants with similar syntax to C:

# At the top of the script...
use enum qw( YR=0 MO DM DY=7 WK );

# ...later...
my( $yr, $mo, $dm, $dy, $wk ) = @{$values}[ YR, MO, DM, DY, WK ];

[download]

The same effect can be achieved with the constant pragma, though the setup is a little less convenient.

Update: I haven't used enum before, but I like how it seems so familiar to someone who has spent time with C or C++. I discovered it when I went looking for a module that would provide the inlinable functions that constant does, but with a declaration syntax closer to the convenience of C's enums. Imagine that; a Perl programmer going looking for C-like convenience!!! That will never happen again. Anyway, why I'm really happy for having found it is because the module's documentation led me to this: Neil Bowers' blog on "CPAN modules for defining constants".


Dave

In reply to Re^3: Slices from array reference by davido
in thread Slices from array reference by oakb

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