A class/interface cannot implement/extend a type parameter (issues 886 and 887).

A class/interface cannot implement/extend a type parameter (issues 886 and 887).
Added tests.
Committed: https://code.google.com/p/dart/source/detail?r=3122

[hausner, 2012-01-09 18:54:49]

LGTM with comments.

http://codereview.chromium.org/9153006/diff/1/runtime/vm/parser.cc
File runtime/vm/parser.cc (right):

http://codereview.chromium.org/9153006/diff/1/runtime/vm/parser.cc#newcode2517
runtime/vm/parser.cc:2517: ErrorMsg("class '%s' may not extend type parameter
'%s'",
I would print the error at the actual text position of the type. You can
remember the token position after consuming the 'extends' token.

http://codereview.chromium.org/9153006/diff/1/runtime/vm/parser.cc#newcode3015
runtime/vm/parser.cc:3015: ErrorMsg("interface '%s' may not extend type
parameter '%s'",
Would be nice if these error messages were pointing to the actual interface name
that causes the error. At least though I would print the error at interface_pos,
like in the error message at line 3028.

http://codereview.chromium.org/9153006/diff/1/tests/language/src/ImplementTyp...
File tests/language/src/ImplementTypeParameterNegativeTest.dart (right):

http://codereview.chromium.org/9153006/diff/1/tests/language/src/ImplementTyp...
tests/language/src/ImplementTypeParameterNegativeTest.dart:5: class A<T>
implements T { }
Could you add a short comment why this code is supposed to fail? (In the other
tests as well.)

[regis, 2012-01-09 19:19:30]

Thanks!

http://codereview.chromium.org/9153006/diff/1/runtime/vm/parser.cc
File runtime/vm/parser.cc (right):

http://codereview.chromium.org/9153006/diff/1/runtime/vm/parser.cc#newcode2517
runtime/vm/parser.cc:2517: ErrorMsg("class '%s' may not extend type parameter
'%s'",
On 2012/01/09 18:54:49, hausner wrote:
> I would print the error at the actual text position of the type. You can
> remember the token position after consuming the 'extends' token.

Done here and on line 2523 below.

http://codereview.chromium.org/9153006/diff/1/runtime/vm/parser.cc#newcode3015
runtime/vm/parser.cc:3015: ErrorMsg("interface '%s' may not extend type
parameter '%s'",
On 2012/01/09 18:54:49, hausner wrote:
> Would be nice if these error messages were pointing to the actual interface
name
> that causes the error. At least though I would print the error at
interface_pos,
> like in the error message at line 3028.

We should definitely store the position in each type. For now, I use
interface_pos, as you suggested.

http://codereview.chromium.org/9153006/diff/1/tests/language/src/ImplementTyp...
File tests/language/src/ImplementTypeParameterNegativeTest.dart (right):

http://codereview.chromium.org/9153006/diff/1/tests/language/src/ImplementTyp...
tests/language/src/ImplementTypeParameterNegativeTest.dart:5: class A<T>
implements T { }
On 2012/01/09 18:54:49, hausner wrote:
> Could you add a short comment why this code is supposed to fail? (In the other
> tests as well.)

Done.