G'day pvaldes,

In terms of style, I'd say it's perfectly acceptable to embed an expression in a print list. Having said that, if the expression is long or complicated, I'd usually move it out of the print statement. 

$fo ||= 'Roses are red ...';
print "My homework: $fo";

[download]

As others have already pointed out, a FALSE value can be "non empty", so || is probably not the best choice.

# (fo will be updated with a real value in this part)

You'll need to tell us what's going on there. My first guess was that you're perhaps doing something like: 

$ perl -E '
    my $fo = "";
    update($fo);
    print "|$fo|";

    sub update {
        my ($arg) = @_;
        $arg .= "XXX";
    }
'
||

[download]

when what you really wanted was something like: 

$ perl -E '
    my $fo = "";
    update(\$fo);
    print "|$fo|";

    sub update {
        my ($arg) = @_;
        $$arg .= "XXX";
    }
'
|XXX|

[download]

But there would be dozens of reasons why your update could be returning a "forrible" value. :-)

— Ken

In reply to Re: conditional print. Is correct to use it? by kcott
in thread conditional print. Is correct to use it? by pvaldes

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