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| 1 | namespace Semantic.Symbols is | |
| 2 | use System.Exception; | |
| 3 | use System.NotImplementedException; | |
| 4 | ||
| 5 | use IoC; | |
| 6 | use Logging; | |
| 7 | use Source; | |
| 8 | ||
| 9 | use IR.Values.Value; | |
| 10 | ||
| 11 | use Types.Type; | |
| 12 | ||
| 13 | // Holds same-name types declared at different generic-argument counts | |
| 14 | // under one identifier. `class Foo is` (0 arguments) and `class Foo[T] is` | |
| 15 | // (1 argument) both live as direct members of the enclosing scope. A | |
| 16 | // reflected `Foo` and `Foo`1` from the same .NET namespace join the | |
| 17 | // group via the import side. | |
| 18 | // | |
| 19 | // The group is transparent to lookup paths that resolve to a single | |
| 20 | // member: GENERIC_APPLICATION picks the member matching the supplied | |
| 21 | // argument count; bare-name resolution picks the no-arguments member | |
| 22 | // when one exists. Sites that genuinely care that they got a group | |
| 23 | // (completion, hover) test `isa TYPE_GROUP`. | |
| 24 | class TYPE_GROUP: Scoped is | |
| 25 | _classies: Collections.LIST[Classy]; | |
| 26 | ||
| 27 | count: int => _classies.count; | |
| 28 | is_empty: bool => _classies.count == 0; | |
| 29 | ||
| 30 | short_description: string => name; | |
| 31 | ||
| 32 | describe(context: DESCRIBE_CONTEXT) -> SignaturePart => | |
| 33 | PARTS.name(self); | |
| 34 | ||
| 35 | describe_kind(context: DESCRIBE_CONTEXT) -> string? => "type group"; | |
| 36 | symbol_kind: SymbolKind => SymbolKind.CLASS; | |
| 37 | completion_kind: CompletionKind => CompletionKind.CLASS; | |
| 38 | ||
| 39 | is_type_group: bool => true; | |
| 40 | is_type: bool => true; | |
| 41 | ||
| 42 | classies: Collections.List[Classy] => _classies; | |
| 43 | ||
| 44 | init(location: LOCATION, owner: Scope, name: string) is | |
| 45 | super.init(location, owner, name); | |
| 46 | ||
| 47 | _classies = Collections.LIST[Classy](); | |
| 48 | si | |
| 49 | ||
| 50 | add(classy: Classy) is | |
| 51 | classy.has_argument_count_siblings = true; | |
| 52 | _classies.add(classy); | |
| 53 | si | |
| 54 | ||
| 55 | remove(classy: Classy) is | |
| 56 | _classies.remove(classy); | |
| 57 | si | |
| 58 | ||
| 59 | // Returns the member whose generic-argument count matches `count`, | |
| 60 | // or null if no such member exists in the group. | |
| 61 | find_by_generic_arguments_count(count: int) -> Classy? is | |
| 62 | for c in _classies do | |
| 63 | if c.argument_names.count == count then | |
| 64 | return c; | |
| 65 | fi | |
| 66 | od | |
| 67 | ||
| 68 | return null; | |
| 69 | si | |
| 70 | ||
| 71 | // The group's sole member with generic arguments, or null when there | |
| 72 | // is not exactly one. The common reflected shape for a name shared | |
| 73 | // across arities is one non-generic member (e.g. the static | |
| 74 | // `KeyValuePair` factory class) plus one generic type | |
| 75 | // (`KeyValuePair[K,V]`); a constructor call on the bare name resolves | |
| 76 | // to that generic member so its arguments can be inferred. | |
| 77 | sole_generic_member() -> Classy? is | |
| 78 | let result: Classy? mut = null; | |
| 79 | ||
| 80 | for c in _classies do | |
| 81 | if c.argument_names.count > 0 then | |
| 82 | if result? then | |
| 83 | return null; | |
| 84 | fi | |
| 85 | ||
| 86 | result = c; | |
| 87 | fi | |
| 88 | od | |
| 89 | ||
| 90 | return result; | |
| 91 | si | |
| 92 | ||
| 93 | // The generic-argument counts currently represented in the group, | |
| 94 | // sorted ascending. Used for diagnostics ("expected 0 or 2 type | |
| 95 | // arguments but found 1"). | |
| 96 | generic_arguments_counts: Collections.List[int] is | |
| 97 | let result = Collections.LIST[int](); | |
| 98 | ||
| 99 | for c in _classies do | |
| 100 | result.add(c.argument_names.count); | |
| 101 | od | |
| 102 | ||
| 103 | result.sort(); | |
| 104 | ||
| 105 | return result; | |
| 106 | si | |
| 107 | ||
| 108 | // If the group holds exactly one member, return it; else return | |
| 109 | // self. Callers that don't need group-awareness use this to | |
| 110 | // transparently see a single Classy. | |
| 111 | collapse_group_if_single_member() -> Symbol => | |
| 112 | if _classies.count == 1 then | |
| 113 | _classies[0]; | |
| 114 | else | |
| 115 | self; | |
| 116 | fi; | |
| 117 | ||
| 118 | find_member(name: string) -> Symbol? is | |
| 119 | // Member lookup on a group falls through to the no-arguments | |
| 120 | // member if one exists. Common case: `Foo.NESTED` when both | |
| 121 | // `Foo` and `Foo[T]` exist and the user means the non-generic | |
| 122 | // one. | |
| 123 | let bare = find_by_generic_arguments_count(0); | |
| 124 | ||
| 125 | if bare? then | |
| 126 | return bare.find_member(name); | |
| 127 | fi | |
| 128 | ||
| 129 | return null; | |
| 130 | si | |
| 131 | ||
| 132 | // A bare-name load of a group means the no-arguments member. | |
| 133 | // Resolution sites (`compile_access`, GENERIC_APPLICATION, | |
| 134 | // `resolve_type_expressions`) normally collapse the group before | |
| 135 | // it reaches a load, but this keeps a stray group from | |
| 136 | // producing a `Load.SYMBOL` whose `type` cast fails — a group | |
| 137 | // is not `Types.Typed`. | |
| 138 | load(location: LOCATION, from: Value?, loader: SYMBOL_LOADER) -> Value is | |
| 139 | let bare = find_by_generic_arguments_count(0); | |
| 140 | ||
| 141 | if bare? then | |
| 142 | return bare.load(location, from, loader); | |
| 143 | fi | |
| 144 | ||
| 145 | return IR.Values.DUMMY(Types.ERROR(), location); | |
| 146 | si | |
| 147 | ||
| 148 | to_string() -> string => | |
| 149 | "{description} [{_classies|}]"; | |
| 150 | si | |
| 151 | si |