To simplify: let's say I have an array of numbers, some positive, some negative, some zero, that I want to print out like so:

  +1  -4  +3   0  -2   0 -14

That is to say, with '+' signs before each positive number. If I use the following code:

my @nums = qw ( 1 -4 3 0 -2 0 -14 );
printf '%+4d', $_ for @nums;

[download]

I get plus signs in front of my zeros, which I don't want:

  +1  -4  +3  +0  -2  +0 -14

In the docs for (s)printf - which incidentally I find very sparse - it says that the '+' flag is used to "prefix (a) positive number with a plus sign". I'm not a mathematician, so I'm prepared to accept that zero is a positive number. But I still don't wan't plus signs in front of my zeros :-(

I've come up with various solutions, and for the moment, my code looks like this:

printf $_ == 0 ? ( '%4d', $_ ) : ( '%+4d', $_ ) for @nums;

...but the more I stare at it, the more it looks like line noise. OK, I could expand and comment it; however, my question is, is there a better way?

TIA

dave

In reply to (s)printf question: eliminating plus sign before zeros by Not_a_Number

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