Replacing deprecated “defined(@array)” in a ternary operation

Question

I have the following code which needs to be corrected, as defined(@array) is deprecated in the latest Perl.

my @inputs = (
    ( defined @{$padSrc-         


        

Answer 1

defined(@array) has never done what it looks like it does. It always just returns whether @array is non-empty.

perl5.10.1 -E 'say defined(@foo)'                # ""
perl5.10.1 -E '@foo=(); say defined(@foo)'       # ""
perl5.10.1 -E '@foo=(42); say defined(@foo)'     # "1"
perl5.10.1 -E '@foo=(undef); say defined(@foo)'  # "1"

Anywhere that you test defined(@array) in your code, you can replace it with @array != 0 or scalar(@array) and your code will work exactly the same (plus or minus some deprecation warnings).

As if (condition) ... or (condition) ? expr1 : expr2 or while (condition) always evaluate condition in scalar context, the scalar is optional in these constructions, and you can replace, say if (defined(@foo)) with if (@foo).