No, that's normal. Yes, things may/will change in perl 6 (that is a tautology). Compare references using the numeric equality operator. See Re: Why isn't ->can() curried? and Re: Why isn't ->can() curried? for more on comparing references. [Added adrianh has an interesting observation regarding this in Re^3: Comparing references to sub's.]

_detect_type('unzipped.txt') == \&open_unzipped
_detect_type('zipped.zip') == \&open_zipped
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