From @AlexDaniel

Code​:
say 1.map​: { Slip }

Result​:
Parameter '$slip' requires an instance of type Slip, but a type object was
passed. Did you forget a .new?
  in block <unit> at -e​:1

The problem is that it mentions some internal �$slip� parameter.

In this simple case it is pretty clear what is happening, but imagine the
type object coming from somewhere else. Perhaps there is a way to make the
error message slightly better?

From @LLFourn

2¢
I don't think this should be an error. A Slip type is a kinda odd thing to
be mapping but it should work.

quick look​:

https://github.com/rakudo/rakudo/blob/a61bbddc005d0188e2409a9ef8feee0c9551ab08/src/core/Any-iterable-methods.pm#L121

It just checks whether it's a Slip type but should also be checking that
it's defined.

On Sat, Dec 12, 2015 at 2​:30 PM Alex Jakimenko <perl6-bugs-followup@​perl.org>
wrote​:

# New Ticket Created by Alex Jakimenko
# Please include the string​: [perl #​126883]
# in the subject line of all future correspondence about this issue.
# <URL​: https://rt-archive.perl.org/perl6/Ticket/Display.html?id=126883 >

Code​:
say 1.map​: { Slip }

Result​:
Parameter '$slip' requires an instance of type Slip, but a type object was
passed. Did you forget a .new?
in block <unit> at -e​:1

The problem is that it mentions some internal �$slip� parameter.

In this simple case it is pretty clear what is happening, but imagine the
type object coming from somewhere else. Perhaps there is a way to make the
error message slightly better?

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

From @geekosaur

On Fri, Dec 11, 2015 at 11​:55 PM, Lloyd Fournier <lloyd.fourn@​gmail.com>
wrote​:

I don't think this should be an error. A Slip type is a kinda odd thing to
be mapping but it should work.

It's not mapping over Slips in general; it's mapping over an *undefined*
Slip. I'd similarly expect some kind of error or at least warning for
mapping over an undefined list.

--
brandon s allbery kf8nh sine nomine associates
allbery.b@​gmail.com ballbery@​sinenomine.net
unix, openafs, kerberos, infrastructure, xmonad http://sinenomine.net

From @LLFourn

yep by Slip type I meant a Slip type object ie undefined Slip (as opposed
to a Slip instance).

I don't really understand why it should be an error or warning.

1.map​: { Any } # ((Any))
1.map​: { Slip } # shouldn't this be ((Slip)), What's wrong with this?

On Sat, Dec 12, 2015 at 4​:00 PM Brandon Allbery <allbery.b@​gmail.com> wrote​:

On Fri, Dec 11, 2015 at 11​:55 PM, Lloyd Fournier <lloyd.fourn@​gmail.com>
wrote​:

I don't think this should be an error. A Slip type is a kinda odd thing
to be mapping but it should work.

It's not mapping over Slips in general; it's mapping over an *undefined*
Slip. I'd similarly expect some kind of error or at least warning for
mapping over an undefined list.

--
brandon s allbery kf8nh sine nomine
associates
allbery.b@​gmail.com
ballbery@​sinenomine.net
unix, openafs, kerberos, infrastructure, xmonad
http://sinenomine.net

From @LLFourn

test​:
Raku/roast@c205f71

On Sat, Dec 12, 2015 at 8​:13 PM Elizabeth Mattijsen <liz@​dijkmat.nl> wrote​:

Fixed with 502b886e8d14dbd51b5 , needs tests

$ 6 'say 1.map​: { Slip }'
((Slip))

On 12 Dec 2015, at 03​:30, Alex Jakimenko (via RT) <
perl6-bugs-followup@​perl.org> wrote​:

# New Ticket Created by Alex Jakimenko
# Please include the string​: [perl #​126883]
# in the subject line of all future correspondence about this issue.
# <URL​: https://rt-archive.perl.org/perl6/Ticket/Display.html?id=126883 >

Code​:
say 1.map​: { Slip }

Result​:
Parameter '$slip' requires an instance of type Slip, but a type object
was
passed. Did you forget a .new?
in block <unit> at -e​:1

The problem is that it mentions some internal �$slip� parameter.

In this simple case it is pretty clear what is happening, but imagine the
type object coming from somewhere else. Perhaps there is a way to make
the
error message slightly better?

From @AlexDaniel

This was fixed in rakudo/rakudo@502b886

Not sure why it's still not closed. Closing.

On 2015-12-12 20​:45​:06, lloyd.fourn@​gmail.com wrote​:

test​:
Raku/roast@c205f71

On Sat, Dec 12, 2015 at 8​:13 PM Elizabeth Mattijsen <liz@​dijkmat.nl>
wrote​:

Fixed with 502b886e8d14dbd51b5 , needs tests

$ 6 'say 1.map​: { Slip }'
((Slip))

On 12 Dec 2015, at 03​:30, Alex Jakimenko (via RT) <
perl6-bugs-followup@​perl.org> wrote​:

# New Ticket Created by Alex Jakimenko
# Please include the string​: [perl #​126883]
# in the subject line of all future correspondence about this
issue.
# <URL​: https://rt-archive.perl.org/perl6/Ticket/Display.html?id=126883 >

Code​:
say 1.map​: { Slip }

Result​:
Parameter '$slip' requires an instance of type Slip, but a type
object
was
passed. Did you forget a .new?
in block <unit> at -e​:1

The problem is that it mentions some internal “$slip” parameter.

In this simple case it is pretty clear what is happening, but
imagine the
type object coming from somewhere else. Perhaps there is a way to
make
the
error message slightly better?

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