library/ops.m:
Instead of an op_table mapping a string to a list of one or more op_infos,
make it map the string to a single structure, the op_infos, which has
four slots, one each for infix, binary prefix, prefix and postfix
op information. This allows parsers and unparsers to go directly to
the kind of operator (e.g. infix or prefix) that they are interested in.
NEWS:
Announce the change.
compiler/parse_tree_out_term.m:
library/mercury_term_parser.m:
library/pretty_printer.m:
library/stream.string_writer.m:
library/string.to_string.m:
samples/calculator2.m:
tests/hard_coded/bug383.m:
Conform to the change. In several places, the new operator representation
allows the replacement of loops with direct lookups, and the replacement
of if-then-else chains with switches.
Add reminders about keeping two predicates in sync.
library/io.m:
Delete the set_io_table predicate, which did nothing and was never
called from anywhere, and the get_io_table predicate, which always
returned the same op_table. They were in io.m's interface, but in the
not-publicly-visible part of the interface.
library/ops.m:
Rename the lookup_op method to is_op.
Delete references to the predicates deleted from io.m.
NEWS:
Announce the lookup_op->is_op rename.
compiler/parse_tree_out_term.m:
library/mercury_term_parser.m:
library/string.to_string.m:
library/term_io.m:
samples/calculator2.m:
tests/hard_coded/bug383.m:
Conform to the lookup_op->is_op rename.
Replace calls to get_io_table with code that directly gets
the Mercury op table.
In parse_tree_out_term.m, call the predicates operating on the
Mercury op table directly, not through the op_table type class.
In mercury_term_parser.m, update some comments.
In term_io.m, use OpTable to refer to op_tables.
tests/hard_coded/stdlib_init.{m,exp}:
Don't test get_io_table.
Mercury inherited its original system of operator priorities from Prolog,
because during its initial development, we wanted to be able execute
the Mercury compiler using NU-Prolog and later SICStus Prolog.
That consideration has long been obsolete, and now we may fix the
design error that gifted Prolog with its counter-intuitive system
of operator priorities, in which higher *numerical* operator priorities
mean lower *actual* priorities. This diff does that.
library/ops.m:
Change the meaning of operator priorities, to make higher numerical
priorities mean also higher actual priorities.
This semantic change requires corresponding changes in any other module
that uses ops.m. To force this change to occur, change the type
representing priorities from being a synonym for a bare int to being
a notag wrapper around an uint.
The old "assoc" type had a misleading name, since it is related to
associativity but is not itself a representation of associativity.
Its two function symbols, which used to be just "x" and "y", meant that
the priority of an argument must be (respectively) greater than,
or greater than equal to, the priority of the operator. So rename
x to arg_gt, y to arg_ge, and assoc to arg_prio_gt_or_ge.
Rename the old adjust_priority_for_assoc predicate to min_priority_for_arg,
which better expresses its semantics. Turn it into a function, since
some of its users want it that way, and move its declaration to the
public part of the interface.
Add a method named tightest_op_priority to replace the use of 0
as a priority.
Rename the max_priority method as the loosest_op_priority method.
Add a method named universal_priority to replace the use of
max_priority + 1 as a priority.
Add a function to return the priority of the comma operator,
to allow other modules to stop hardcoding it.
Add operations for comparing priorities and for incrementing/decrementing
priorities.
Change the prefix on the names of the predicates that take op_infos
as inputs from "mercury_op_table_" to "op_infos_", since the old prefix
was misleading.
Add a note on an significant old problem with an exported type synonym.
library/mercury_term_parser.m:
Conform to the changes above.
Delete unnecessary module qualifiers, since they were just clutter.
Add "XXX OPS" to note further opportunities for improvement.
library/pprint.m:
Conform to the changes above.
Rename a function to avoid ambiguity.
library/pretty_printer.m:
library/stream.string_writer.m:
library/string.to_string.m:
library/term_io.m:
Conform to the changes above.
library/string.m:
Add a note on an significant old problem.
NEWS:
Announce the user-visible changes.
tests/hard_coded/bug383.m:
Update this test case to use the new system of operator priorities.
tests/hard_coded/term_io_test.{m,inp}:
Fix white space.
extras/old_library_modules/old_mercury_term_parser.m:
extras/old_library_modules/old_ops.m:
The old contents of the mercury_term_parser and ops modules,
in case anyone wants to continue using them instead of updating
their code to use their updated equivalents.
samples/calculator2.m:
Import the old versions of mercury_term_parser and ops.
Their replacements are the corresponding predicates in mercury_term_parser.m,
which they forwarded all their work to anyway.
library/term_io.m:
As above.
library/mercury_term_parser.m:
Move the definition of a type needed by the read_term* predicates
here from term_io.m.
NEWS:
Document the deletion.
browser/interactive_query.m:
compiler/fact_table.m:
compiler/parse_module.m:
compiler/recompilation.used_file.m:
library/io.m:
Conform to the change above.
tests/debugger/interpreter.m:
tests/general/interpreter.m:
Use read_term* from mercury_term_parser, not term_io.
These two tests started out as versions of the same file once upon a time,
but have diverged since. Replace them both with a single version that
works in both test directories, and has updated programming style.
tests/debugger/interpreter.exp2:
tests/debugger/interpreter.inp:
tests/general/interpreter.exp:
Conform to the changes (renames of some predicates, inlining of others,
using explicit streams, never complaining about empty argument lists,
and always printing query results) in interpreter.m.
tests/hard_coded/bug383.m:
tests/hard_coded/term_io_test.m:
Use read_term* from mercury_term_parser, not term_io.
In bug383.m, resolve an old type ambiguity to avoid a warning.
This was Mantis bug #383.
compiler/ml_string_switch.m:
For model_non switches in MLDS grades, a failure is indicated by
a fall through. This can be represented by an empty sequence of
MLDS statements, but the code that generated string trie switches
took such an empty sequence to mean that the switch could not fail.
Fix this incorrect assumption.
tests/hard_coded/bug383.{m,inp,exp}:
A regression test for the bug.
tests/hard_coded/Mmakefile:
Enable the new test case.
