function prototypes using array of subset type give type error

[p6rt]

Migrated from rt.perl.org#131381 (status was 'new')

Searchable as RT131381$

[p6rt]

From danielcliffordmiller@gmail.com

This is Rakudo version 2017.04.3 built on MoarVM version 2017.04-53-g66c6dda

implementing Perl 6.c

[p6rt]

From danielcliffordmiller@gmail.com

test.pl6

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From @zoffixznet

OP's code in the attachment​:

subset PositiveInt of Int where * > 0;

my Int $i = 4;
my Int @​i = (2,4);

my PositiveInt $p = 6;
my PositiveInt @​p = (2,4);

sub handle-ints (Int @​i) {}
sub handle-positive-ints (PositiveInt @​p) {}

$i = -5;
#$p = -5; # should fail

handle-ints(@​i);
#handle-ints( (2.2, 1.1) ); # should fail

handle-positive-ints(@​p); # this fails?

[p6rt]

From @zoffixznet

Golfed version​:

m​: -> UInt @​ {}(Array[UInt].new)
rakudo-moar 8ec181​: OUTPUT​: «Constraint type check failed in binding to parameter '<anon>'; expected UInt but got Array[UInt] (Array[UInt].new())␤ in block <unit> at <tmp> line 1␤␤»

Works if you don't use `@​` sigil​:

m​: -> Positional[UInt] {}(Array[UInt].new)
rakudo-moar 8ec181​: ( no output )

[p6rt]

From @zoffixznet

Fudged test added​: Raku/roast#273