If this is a problem you can call all subroutines in array context and examine the first and possible remainder of the array elements for expected return values. 
@ret = somesub();
if (ref $ret[0] eq 'HASH') { .... }
elsif (ref $ret[0] eq 'ARRAY') { .... }

[download]
etc. Messy but would take care of the problem. This is how I handle some XML data structures deparsed from API calls to certain applications that can return an array of hashrefs, an arrayref of hashrefs, a single hashref or undefined.

In reply to Re^3: check for wantarray? by bageler
in thread check for wantarray? by KurtZ

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