I often will use for instead of map for generating lists, especially when I am in the process of developing the code. Once I've got things figured out I might go back and re-code the loop as a map.

Using for has the following advantages:

• you have more control and options over loop execution (last, next, etc.)
• you can use your own more descriptive named lexical instead of $_
• it's more readable (especially for non-perl experts)

If the list-generation logic is just a simple transformation, I'll just opt for a map implementation. Once, however, the logic becomes more complex, an explicit for loop begins to look more attractive. For instance, which of the following do you find easier to understand?

my @result = map { f($_) ? g($_) : () } @list;

# or:
my @result;
for (@list) {
  push(@result, g($_)) if (f($_));
}
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