I often use default values for scalar variables, e. g.

$val = $x || $default

Now I tried this for lists, but it doesn't work - or, to be precise, it works only if the first list is empty, because otherwise the first list is interpreted in scalar context: 

@a = ();
@b = qw (one two three);
@c = qw (four five);

@d = @a || @c; #gives ('four', 'five') - OK
@d = @b || @c; #gives ('3') - yikes!

[download]

Can I inhibit the interpretation of the first list as scalar? Or is the only way to get the desired behaviour: 

@list = @a;
@list = @default unless @list;

[download]

Thanks for your suggestions,

pike

In reply to default values for lists by pike

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