Re^2: Distinguish between missing and undefined arguments with subroutine signatures

P5P is considering to drop the population of @_ when signatures are used

But only after alternative facilities for argument instrospection have been provided. See the proposal on the p5p mailing list.

In particular, in

sub foo($x,  ??$has_y, $y = 0) { ... }
[download]

$has_y is true if and only if a second arg is passed to the sub.

Dave.

Comment on Re^2: Distinguish between missing and undefined arguments with subroutine signatures Download Code

Replies are listed 'Best First'.
Re^3: Distinguish between missing and undefined arguments with subroutine signatures by jo37 (Deacon) on Dec 27, 2020 at 20:31 UTC
`sub foo($x, ??$has_y, $y = 0) { ... }` [download] Great! That's it. (Or better: Will be) Greetings, -jo `$gryYup$d0ylprbpriprrYpkJl2xyl~rzg??P~5lp2hyl0p$`	[reply] [d/l]


laziness, impatience, and hubris
	PerlMonks