if they are not overridable then it returns undef - but then please note that the inverse implication does not hold.

yes, those with an undefined prototype are still overridable, but you can't make the replacement function behave like the original one in every way (due to parsing issues), for example exec/system's indirect object syntax.

BTW, I was once also in desperate need to override the filetest operators... so I'm pretty sure it cannot be achieved with the current implementation — but also see the patch mentioned in footnote 2 in the post I linked to.

In reply to Re: Previously unseen error in connection with -X functions by almut
in thread Previously unseen error in connection with -X functions by blazar

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