mirror of
https://github.com/Mercury-Language/mercury.git
synced 2026-04-21 12:23:44 +00:00
2ac8465659
The motivation for this diff was that I wanted the compiler to generate
a warning if a module declared the same type twice. (During the cleanup
of unify_proc.m I did recently, I found and fixed such a duplicate
declaration.)
compiler/add_type.m:
The old code of module_add_type_defn was not just long (210+ lines),
it is also very complex.
Part of this complexity was sort-of justified. It dealt with adding
three separate kinds of item_type_defns: abstract type "definitions",
which are actually declarations; the definitions of Mercury types,
and the definitions of foreign types. A single type could have more than
one of these (e.g. declaration and a definition, or a Mercury definition
and a foreign definition), and it had to be prepared to process these
in any order.
Part of this complexity was self-inflicted. The parts of the predicate
that dealt with the same kind of definition were not always next to each
other, and for some parts, it wasn't even clear *what* kind of definition
it was dealing with. It did the same tests on both the old and updated
versions of definitions, when those definitions were guaranteed to be
identical; the "updating" predicate was a no-op. And it used completely
different code for detecting and handling related errors.
This diff fixes the above problems. It separates the task of adding
an item_type_defn to the HLDS into three subtasks, done in three separate
predicates: adding type declarations, adding Mercury definitions, and
adding foreign definitions. It specializes each predicate to its task,
and simplifies its decision flow. It also delegates the creation of
(most) error messages to separate predicates. Together, these changes
make each of module_add_type_defn_{abstract,mercury,foreign} easily
understandable.
Generate a warning if a type is declared twice, i.e. if e.g.
":- type x." is followed by another ":- type x.".
Call module_info_incr_errors to register the presence of errors in just
one central place. (Before, some of the places that generated error
messages incremented the error count, and some places didn't.)
Improve the wording of some error messages.
Refer to type names in error messages by unqualified sym_names
in cases where the module qualifier being elided is obvious from
the name of the module being compiled.
Add documentation.
Add descriptions of potential future improvements.
Add some XXXs at places that I think deserve them.
Give some predicates and variables better names.
compiler/prog_data.m:
Change the parse tree representation of type definitions by
explicitly specifying a type for storing the contents of each kind
of type definition.
compiler/hlds_data.m:
Give a predicate a better name.
Use one of the new types in prog_data.m in the HLDS version of type
definitions, to minimize differences between the parse tree and HLDS
versions.
compiler/add_foreign_enum.m:
compiler/add_pragma.m:
compiler/add_special_pred.m:
compiler/check_typeclass.m:
compiler/du_type_layout.m:
compiler/equiv_type.m:
compiler/equiv_type_hlds.m:
compiler/foreign.m:
compiler/get_dependencies.m:
compiler/hlds_code_util.m:
compiler/hlds_out_module.m:
compiler/inst_check.m:
compiler/intermod.m:
compiler/item_util.m:
compiler/make_hlds_passes.m:
compiler/make_hlds_separate_items.m:
compiler/make_tags.m:
compiler/ml_type_gen.m:
compiler/ml_unify_gen.m:
compiler/module_qual.qualify_items.m:
compiler/parse_pragma.m:
compiler/parse_tree_out.m:
compiler/parse_type_defn.m:
compiler/post_term_analysis.m:
compiler/recompilation.check.m:
compiler/recompilation.usage.m:
compiler/recompilation.version.m:
compiler/resolve_unify_functor.m:
compiler/simplify_goal_ite.m:
compiler/special_pred.m:
compiler/switch_util.m:
compiler/term_norm.m:
compiler/type_ctor_info.m:
compiler/type_util.m:
compiler/unify_proc.m:
compiler/unused_imports.m:
compiler/write_module_interface_files.m:
compiler/xml_documentation.m:
Conform to the changes in prog_data.m.
library/io.m:
library/store.m:
Delete duplicate type declarations that add_type.m now complains about.
tests/invalid/bad_foreign_type.{m,err_exp}:
Extend this test to test the new warning.
Expect the updated versions of some error messages.
tests/invalid/extra_info_prompt.err_exp:
tests/invalid/foreign_type_visibility.err_exp:
tests/invalid/user_eq_dummy.err_exp:
Expect the updated versions of some error messages.
5 lines
246 B
Plaintext
5 lines
246 B
Plaintext
extra_info_prompt.m:010: Error: the type `foo'/0 contains no information, and
|
|
extra_info_prompt.m:010: as such it is not allowed to have user-defined
|
|
extra_info_prompt.m:010: equality or comparison.
|
|
For more information, recompile with `-E'.
|