mercury/instance_var_bug.err_exp at 55cf491e34eef8a0499330c3520e8e372fc8774e - mercury - Steepath Git Private Instance

mercurylang/mercury

mirror of https://github.com/Mercury-Language/mercury.git synced 2026-04-25 06:14:18 +00:00

Files

Julien Fischer dc1e59e48b Fix a bug (#27 ) reported by Ralph. The compiler was aborting on

Estimated hours taken: 1
Branches: main

Fix a bug (#27) reported by Ralph.  The compiler was aborting on
instances that contained type variables that were not wrapped in functors.
The problem is that the name mangling scheme used to mangle the names of
method wrapper predicates cannot handle instances that contain unwrapped
type variables.  The compiler already has code to check for this, but that
check was not being performed until *after* it had attempted to introduce
the method wrapper predicates.

The fix is to reorder the phases of check_typeclass.m so that we perform
the check on the types in an instance first and only run the remaining
phases if the first one succeeds.

compiler/check_typeclass.m:
	Reorder the phases within this module so that we don't attempt
	to introduce method wrapper predicates for invalid instances.

	Update the documentation in this module to conform to the above
	change.

	Remove some unnecessary module qualification.

tests/invalid/Mercury.options:
tests/invalid/Mmakefile:
tests/invalid/instance_var_bug.{m,err_exp}:
	Test for the above bug.

tests/invalid/bad_instance.err_exp:
	Update this.  The error message for the missing concrete instance
	won't be emitted with the above change.  Note, we have a separate
	test case, tests/invalid/missing_concrete_instance, that exercises
	that error message.

2007-11-14 04:00:06 +00:00

5 lines

274 B

Plaintext

Raw Blame History

 instance_var_bug.m:014: In instance declaration for `instance_var_bug.tc(V)':
 instance_var_bug.m:014:   the first arg is a type variable
 instance_var_bug.m:014:   types in instance declarations must be functors with
 instance_var_bug.m:014:   distinct variables as arguments