Your list of numbers is a list; the problem is that pop is the source of the surrounding context and provides a scalar one. If you check the prototype, pop is ";+" and + is a bit weird. Thus quoth perlsub: 

    The "+" prototype is a special alternative to "$" that will act li
+ke
    "\[@%]" when given a literal array or hash variable, but will othe
+rwise
    force scalar context on the argument. This is useful for functions
+ which
    should accept either a literal array or an array reference as the
    argument:

[download]

Update: Tweaked formatting.

The cake is a lie.
The cake is a lie.
The cake is a lie.

In reply to Re: passing an array without a name to pop() by Fletch
in thread passing an array without a name to pop() by TieUpYourCamel

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