Hi,
Can someone please review this?
---
Estimated hours taken: 2
When a constructor cannot be found in the cons_table, check for occurences
of the same functor with a different arity in the table and give a more
accurate error message in that case.
compiler/typecheck.m:
Before emitting an error message about an unfound constructor, check
the cons_table for occurences of the same functor with different
arity. If there are any such occurences, mention them to the user.
Rename report_error_pred_num_right_args/3 to
report_error_right_num_args/3, so that its use to print out the
right number of arguments for constructors makes a little more sense.
Index: typecheck.m
===================================================================
RCS file: /home/staff/zs/imp/mercury/compiler/typecheck.m,v
retrieving revision 1.195
diff -u -r1.195 typecheck.m
--- typecheck.m 1997/04/17 11:06:49 1.195
+++ typecheck.m 1997/04/18 07:08:07
@@ -29,7 +29,7 @@
%
% 2. For accumulating typecheck_infos, which contain:
% - an io_state, which is modified if we need to
-% to write out an error message
+% write out an error message
% - various semi-global info which doesn't change often,
% namely the pred_id and term__context of the clause
% we are type-checking
@@ -3478,7 +3478,7 @@
io__write_string(" error: wrong number of arguments ("),
io__write_int(Arity),
io__write_string("; should be "),
- report_error_pred_num_right_args(Arities),
+ report_error_right_num_args(Arities),
io__write_string(")\n"),
{ typecheck_info_get_context(TypeCheckInfo, Context) },
prog_out__write_context(Context),
@@ -3486,11 +3486,11 @@
prog_out__write_sym_name(Name),
io__write_string("'.\n").
-:- pred report_error_pred_num_right_args(list(int), io__state, io__state).
-:- mode report_error_pred_num_right_args(in, di, uo) is det.
+:- pred report_error_right_num_args(list(int), io__state, io__state).
+:- mode report_error_right_num_args(in, di, uo) is det.
-report_error_pred_num_right_args([]) --> [].
-report_error_pred_num_right_args([Arity | Arities]) -->
+report_error_right_num_args([]) --> [].
+report_error_right_num_args([Arity | Arities]) -->
io__write_int(Arity),
( { Arities = [] } ->
[]
@@ -3499,7 +3499,7 @@
;
io__write_string(", ")
),
- report_error_pred_num_right_args(Arities).
+ report_error_right_num_args(Arities).
:- pred report_error_undef_cons(typecheck_info, cons_id, int, io__state,
io__state).
@@ -3577,12 +3577,42 @@
;
[]
)
- ;
- io__write_string(" error: undefined symbol `"),
- { strip_builtin_qualifier_from_cons_id(Functor, Functor1) },
- hlds_out__write_cons_id(Functor1),
- io__write_string("'.\n")
+ ;
+ (
+ { Functor = cons(Constructor, Arity) },
+ { typecheck_info_get_ctors(TypeCheckInfo, ConsTable) },
+ { solutions(lambda([N::out] is nondet,
+ map__member(ConsTable,
+ cons(Constructor, N),
+ _)),
+ ActualArities) },
+ { ActualArities = [_|_] }
+ ->
+ report_wrong_arity_constructor(Constructor, Arity,
+ ActualArities, Context)
+ ;
+ io__write_string(" error: undefined symbol `"),
+ { strip_builtin_qualifier_from_cons_id(Functor,
+ Functor1) },
+ hlds_out__write_cons_id(Functor1),
+ io__write_string("'.\n")
+ )
).
+
+:- pred report_wrong_arity_constructor(sym_name, arity, list(int),
+ term__context, io__state, io__state).
+:- mode report_wrong_arity_constructor(in, in, in, in, di, uo) is det.
+
+report_wrong_arity_constructor(Name, Arity, ActualArities, Context) -->
+ io__write_string(" error: wrong number of arguments ("),
+ io__write_int(Arity),
+ io__write_string("; should be "),
+ report_error_right_num_args(ActualArities),
+ io__write_string(")\n"),
+ prog_out__write_context(Context),
+ io__write_string(" in use of constructor `"),
+ prog_out__write_sym_name(Name),
+ io__write_string("'.\n").
% language_builtin(Name, Arity) is true iff Name/Arity
% is the name of a builtin language construct that should be
---
love and cuddles,
dgj
--
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