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| 1 | namespace Semantic.Symbols is | |
| 2 | use System.NotImplementedException | |
| 3 | ||
| 4 | use IoC | |
| 5 | use Logging | |
| 6 | use Source | |
| 7 | ||
| 8 | use IR.Values.Value | |
| 9 | ||
| 10 | use Types.Type | |
| 11 | ||
| 12 | use Ghul.Pipes | |
| 13 | ||
| 14 | class FUNCTION_GROUP: Symbol, Types.Typed is | |
| 15 | _functions: Collections.LIST[Function] | |
| 16 | ||
| 17 | count: int => _functions.count | |
| 18 | is_empty: bool => _functions.count == 0 | |
| 19 | ||
| 20 | short_description: string => "{name}(...)" | |
| 21 | ||
| 22 | describe(context: DESCRIBE_CONTEXT) -> SignaturePart => | |
| 23 | PARTS.sequence([ | |
| 24 | PARTS.name(self), | |
| 25 | PARTS.literal("(...)") | |
| 26 | ]) | |
| 27 | ||
| 28 | describe_kind(context: DESCRIBE_CONTEXT) -> string? => "function group" | |
| 29 | symbol_kind: SymbolKind => SymbolKind.FUNCTION | |
| 30 | completion_kind: CompletionKind => CompletionKind.FUNCTION | |
| 31 | ||
| 32 | is_function_group: bool => true | |
| 33 | ||
| 34 | // A group is what a symbol store holds under its name, so every | |
| 35 | // store-level filter (completion, outline, duplicate checks) sees | |
| 36 | // the group and not its members. It therefore hides exactly when | |
| 37 | // every member is internal; a group holding a visible member stays | |
| 38 | // visible so an overload a user wrote is not hidden alongside one | |
| 39 | // the compiler synthesised. | |
| 40 | is_internal: bool => | |
| 41 | _synthesized \/ | |
| 42 | (_functions.count > 0 /\ (_functions |> all(f => f.is_internal))) | |
| 43 | ||
| 44 | type: Type | |
| 45 | ||
| 46 | set_type(value: Type) is type = value; si | |
| 47 | ||
| 48 | functions: Collections.List[Function] => _functions | |
| 49 | ||
| 50 | init(location: LOCATION, owner: Scope, name: string) is | |
| 51 | super.init(location, owner, name) | |
| 52 | ||
| 53 | type = Types.FUNCTION_GROUP(name, self) | |
| 54 | _functions = Collections.LIST[Function]() | |
| 55 | si | |
| 56 | ||
| 57 | specialize_function_group(type_map: Collections.Map[Symbol,Type], owner: GENERIC) -> FUNCTION_GROUP is | |
| 58 | let result = cast FUNCTION_GROUP?(memberwise_clone())! | |
| 59 | ||
| 60 | result.specialized_from = self | |
| 61 | ||
| 62 | result.type = Types.FUNCTION_GROUP( | |
| 63 | name, | |
| 64 | result | |
| 65 | ) | |
| 66 | ||
| 67 | // Pre-sized empty, filled by add: a LIST(_functions) copy would | |
| 68 | // duplicate every element only for the loop to overwrite them all. | |
| 69 | result._functions = Collections.LIST[Function](_functions.count) | |
| 70 | ||
| 71 | for i in 0.._functions.count do | |
| 72 | result._functions.add(_functions[i].specialize_function(type_map, owner)) | |
| 73 | od | |
| 74 | ||
| 75 | return result | |
| 76 | si | |
| 77 | ||
| 78 | specialize(type_map: Collections.Map[Symbol,Type], owner: GENERIC) -> Symbol => | |
| 79 | specialize_function_group(type_map, owner) | |
| 80 | ||
| 81 | try_specialize( | |
| 82 | location: LOCATION, | |
| 83 | logger: Logger, | |
| 84 | actual_type_arguments: Collections.List[Type] | |
| 85 | ) -> Symbol? | |
| 86 | is | |
| 87 | let result_functions = Collections.LIST[Symbol]() | |
| 88 | let result = FUNCTION_GROUP(location, owner!, name) | |
| 89 | ||
| 90 | let expected_argument_counts = Collections.LIST[int]() | |
| 91 | let arity_matches = Collections.LIST[Function]() | |
| 92 | ||
| 93 | for f in _functions do | |
| 94 | if f.is_generic then | |
| 95 | if f.generic_arguments.count == actual_type_arguments.count then | |
| 96 | arity_matches.add(f) | |
| 97 | else | |
| 98 | expected_argument_counts.add(f.generic_arguments.count) | |
| 99 | fi | |
| 100 | fi | |
| 101 | od | |
| 102 | ||
| 103 | // Overloads whose constraints the type arguments break are not | |
| 104 | // candidates, but only an overload the call could have meant is | |
| 105 | // worth reporting against: when another overload accepts the | |
| 106 | // type arguments, the call's own arguments choose among those. | |
| 107 | let accepting = Collections.LIST[Function]() | |
| 108 | ||
| 109 | for f in arity_matches do | |
| 110 | let use snapshot = logger.speculate_then_backtrack() | |
| 111 | ||
| 112 | GENERIC_CONSTRAINT_CHECKER().check_arguments(location, logger, f, f.generic_argument_names, actual_type_arguments) | |
| 113 | ||
| 114 | let errors = snapshot.backtrack() | |
| 115 | ||
| 116 | if errors.count == 0 then | |
| 117 | accepting.add(f) | |
| 118 | fi | |
| 119 | od | |
| 120 | ||
| 121 | let chosen = if accepting.count > 0 then accepting else arity_matches fi | |
| 122 | ||
| 123 | for f in chosen do | |
| 124 | if accepting.count == 0 then | |
| 125 | GENERIC_CONSTRAINT_CHECKER().check_arguments(location, logger, f, f.generic_argument_names, actual_type_arguments) | |
| 126 | fi | |
| 127 | ||
| 128 | let sf = f.specialize(actual_type_arguments) | |
| 129 | ||
| 130 | result.add(cast Function?(sf)!) | |
| 131 | od | |
| 132 | ||
| 133 | if result.is_empty then | |
| 134 | if expected_argument_counts.count > 0 then | |
| 135 | let counts_string mut = expected_argument_counts |> sort() |> join(", ") | |
| 136 | let last_comma_index = counts_string.last_index_of(", ") | |
| 137 | ||
| 138 | if last_comma_index >= 0 then | |
| 139 | counts_string = counts_string.remove(last_comma_index, 2).insert(last_comma_index, " or ") | |
| 140 | fi | |
| 141 | ||
| 142 | logger.error(location, "expected {counts_string} type arguments but found {actual_type_arguments.count}") | |
| 143 | else | |
| 144 | logger.error(location, "cannot supply type arguments here") | |
| 145 | fi | |
| 146 | ||
| 147 | return null | |
| 148 | fi | |
| 149 | ||
| 150 | return result | |
| 151 | si | |
| 152 | ||
| 153 | remove(function: Function) is | |
| 154 | _functions.remove(function) | |
| 155 | si | |
| 156 | ||
| 157 | add(function: Function) is | |
| 158 | _functions.add(function) | |
| 159 | si | |
| 160 | ||
| 161 | // Combine this group with a same-named group from an enclosing | |
| 162 | // scope: all of this group's functions are kept, and an outer | |
| 163 | // function only joins the overload set when no function here | |
| 164 | // already covers its override class. | |
| 165 | merged_over(outer: FUNCTION_GROUP) -> FUNCTION_GROUP is | |
| 166 | let combined = FUNCTION_GROUP(location, owner!, name) | |
| 167 | ||
| 168 | let seen = Collections.SET[METHOD_OVERRIDE_CLASS]() | |
| 169 | ||
| 170 | for f in _functions do | |
| 171 | seen.add(f.override_class) | |
| 172 | combined.add(f) | |
| 173 | od | |
| 174 | ||
| 175 | for f in outer.functions do | |
| 176 | if !seen.contains(f.override_class) then | |
| 177 | combined.add(f) | |
| 178 | fi | |
| 179 | od | |
| 180 | ||
| 181 | return combined | |
| 182 | si | |
| 183 | ||
| 184 | add(fg: FUNCTION_GROUP) is | |
| 185 | _functions.add_range(fg.functions) | |
| 186 | si | |
| 187 | ||
| 188 | load(location: LOCATION, from: Value?, loader: SYMBOL_LOADER) -> Value => | |
| 189 | loader.load_function_group(from, self) | |
| 190 | ||
| 191 | call(location: Source.LOCATION, from: Value?, arguments: Collections.List[Value], type: Type?, caller: FUNCTION_CALLER) -> IR.Values.Value => throw NotImplementedException("cannot call unresolved function overload group: {self}") | |
| 192 | collapse_group_if_single_member() -> Symbols.Symbol => | |
| 193 | if _functions.count == 1 then | |
| 194 | _functions[0] | |
| 195 | else | |
| 196 | self | |
| 197 | fi | |
| 198 | ||
| 199 | to_string() -> string => | |
| 200 | "{description} [{_functions |> join(", ")}]" | |
| 201 | si | |
| 202 | si |