map { MAPCLAUSE } grep { GREPLCAUSE }

[download]
Can be rewritten as: 
map { GREPCLAUSE ? MAPCLAUSE : () }

[download]
For instance, if you want a list of the squares of the first five odd numbers, either of these will work. 
@odds_squared = map { $_**2 } grep { $_%2 } 1..10;
@odds_squared = map { $_%2 ? $_**2 : () } 1..10;

Result: 1 9 25 49 81

[download]

-Blake

In reply to Re2: Idioms considered harmful by blakem
in thread Idioms considered harmful by rinceWind

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