From naddiseo@gmail.com

If an unknown parameter is passed to assuming, the resulting error message
is uninformative.

Minimal testcase​:
sub (​:@​a) {}.assuming(named => (True))()

Resulting output​: (there is no error message, just a traceback)

  in sub at foo.pl​:1
  in sub CURRIED at src/gen/m-CORE.setting​:3478
  in block <unit> at foo.pl​:1

Interestingly, if the signature is removed, or is changed to a scalar, then
there isn't even a traceback.
The following produce no traceback or error message

sub {}.assuming(named => (True))()
sub (​:$a) {}.assuming(named => True)()

This is perl6 version 2014.09 built on MoarVM version 2014.09

From @moritz

On Thu Dec 25 13​:03​:47 2014, naddiseo@​gmail.com wrote​:

If an unknown parameter is passed to assuming, the resulting error message
is uninformative.

Minimal testcase​:
sub (​:@​a) {}.assuming(named => (True))()

Resulting output​: (there is no error message, just a traceback)

in sub at foo.pl​:1
in sub CURRIED at src/gen/m-CORE.setting​:3478
in block <unit> at foo.pl​:1

Fixed in this commit​:

commit 964e0ddc6dde60bc7b2d0586c813459bd7981cb1
Author​: Moritz Lenz <moritz@​faui2k3.org>
Date​: 2014-12-25 22​:24​:08 +0100

  RT #​123498​: Empty binding error in some cases (partial fix)
 
  On MoarVM, if unexpected named parameters came in through capture or hash
  interpolation, the error message would be empty.
 
  An "if $error" would be false in the case, because $error is usually an empt
  array. Changing it to an "if nqp​::defined($error)" as the rest of the code
  uses should prevent error messages from going missing.

Interestingly, if the signature is removed, or is changed to a scalar, then
there isn't even a traceback.
The following produce no traceback or error message

sub {}.assuming(named => (True))()
sub (​:$a) {}.assuming(named => True)()

This seems to be a separate error, and can be boiled down to​:

sub () {}.(|{​:a})

xfix++ for golfing it down.

The RT System itself - Status changed from 'new' to 'open'

From @jnthn

On Thu Dec 25 14​:08​:04 2014, moritz wrote​:

On Thu Dec 25 13​:03​:47 2014, naddiseo@​gmail.com wrote​:

If an unknown parameter is passed to assuming, the resulting error
message
is uninformative.

Minimal testcase​:
sub (​:@​a) {}.assuming(named => (True))()

Resulting output​: (there is no error message, just a traceback)

in sub at foo.pl​:1
in sub CURRIED at src/gen/m-CORE.setting​:3478
in block <unit> at foo.pl​:1

Fixed in this commit​:

commit 964e0ddc6dde60bc7b2d0586c813459bd7981cb1
Author​: Moritz Lenz <moritz@​faui2k3.org>
Date​: 2014-12-25 22​:24​:08 +0100

RT #​123498​: Empty binding error in some cases (partial fix)

On MoarVM, if unexpected named parameters came in through capture or
hash
interpolation, the error message would be empty.

An "if $error" would be false in the case, because $error is usually
an empt
array. Changing it to an "if nqp​::defined($error)" as the rest of the
code
uses should prevent error messages from going missing.

Interestingly, if the signature is removed, or is changed to a
scalar, then
there isn't even a traceback.
The following produce no traceback or error message

sub {}.assuming(named => (True))()
sub (​:$a) {}.assuming(named => True)()

This seems to be a separate error, and can be boiled down to​:

sub () {}.(|{​:a})

xfix++ for golfing it down.

I ended up rediscovering and fixing this today while working on other issues with flattening named args. Tests passing and unfudged.

/jnthn

@jnthn - Status changed from 'open' to 'resolved'