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| 1 | namespace Syntax.Process is | |
| 2 | use Logging | |
| 3 | use Trees | |
| 4 | ||
| 5 | use Semantic.Types.Type | |
| 6 | ||
| 7 | // Collects, from a tree every body of which has compiled, the type | |
| 8 | // the build settled at each site that left it to inference: a | |
| 9 | // function literal's parameters and return, and a `let` local. The | |
| 10 | // built tree carries nodes the source never had - adapters spliced | |
| 11 | // around literals, synthesised names - so nothing is recorded | |
| 12 | // against a node: each type is keyed by the position the site was | |
| 13 | // written at, and read back against a fresh parse of the file. | |
| 14 | // | |
| 15 | // A type is written only where it can be spelled at that scope: a | |
| 16 | // placeholder that never settled, ERROR, a type parameter foreign | |
| 17 | // to the body, and anything rendering with a synthesised name are | |
| 18 | // all left as written and counted as skipped. | |
| 19 | class INFERRED_ANNOTATIONS: DefaultVisitor, Printer.InferredAnnotations is | |
| 20 | _parameters: Collections.MAP[string, string] | |
| 21 | _returns: Collections.MAP[string, string] | |
| 22 | _locals: Collections.MAP[string, string] | |
| 23 | _type_arguments: Collections.MAP[string, string] | |
| 24 | ||
| 25 | annotated: int | |
| 26 | skipped: int | |
| 27 | ||
| 28 | init( | |
| 29 | logger: Logger, | |
| 30 | symbol_table: Semantic.SYMBOL_TABLE, | |
| 31 | namespaces: Semantic.NAMESPACES | |
| 32 | ) | |
| 33 | is | |
| 34 | super.init(logger, symbol_table, namespaces) | |
| 35 | ||
| 36 | _parameters = Collections.MAP[string, string]() | |
| 37 | _returns = Collections.MAP[string, string]() | |
| 38 | _locals = Collections.MAP[string, string]() | |
| 39 | _type_arguments = Collections.MAP[string, string]() | |
| 40 | si | |
| 41 | ||
| 42 | collect(node: Node) is | |
| 43 | node.walk(self) | |
| 44 | si | |
| 45 | ||
| 46 | parameter_type(location: Source.LOCATION) -> string? => _lookup(_parameters, location) | |
| 47 | return_type(location: Source.LOCATION) -> string? => _lookup(_returns, location) | |
| 48 | local_type(location: Source.LOCATION) -> string? => _lookup(_locals, location) | |
| 49 | ||
| 50 | type_arguments(callee: Source.LOCATION) -> string? is | |
| 51 | let key = _span_key(callee) | |
| 52 | ||
| 53 | if _type_arguments.contains_key(key) then | |
| 54 | return _type_arguments[key] | |
| 55 | fi | |
| 56 | ||
| 57 | return null | |
| 58 | si | |
| 59 | ||
| 60 | visit_default(node: Node) is | |
| 61 | si | |
| 62 | ||
| 63 | // A call or construction whose callee is a plain or qualified | |
| 64 | // name and whose type arguments the build bound rather than the | |
| 65 | // source wrote. The callee's whole span is the key, since a call | |
| 66 | // whose callee is itself a call starts where that inner call does. | |
| 67 | visit(call: Expressions.CALL) is | |
| 68 | let callee = call.function | |
| 69 | ||
| 70 | let callee_name = | |
| 71 | if let identifier: Expressions.IDENTIFIER = callee then | |
| 72 | identifier.identifier.name | |
| 73 | elif let member: Expressions.MEMBER = callee then | |
| 74 | member.identifier.name | |
| 75 | else | |
| 76 | return | |
| 77 | fi | |
| 78 | ||
| 79 | let arguments = _bound_type_arguments(call.value, callee_name) | |
| 80 | ||
| 81 | if !arguments? \/ arguments.count == 0 then | |
| 82 | return | |
| 83 | fi | |
| 84 | ||
| 85 | let spelled = System.Text.StringBuilder() | |
| 86 | ||
| 87 | for type in arguments do | |
| 88 | if let text = _spell(type) then | |
| 89 | if spelled.length > 0 then | |
| 90 | spelled.append(", ") | |
| 91 | fi | |
| 92 | ||
| 93 | spelled.append(text) | |
| 94 | else | |
| 95 | skipped = skipped + 1 | |
| 96 | ||
| 97 | IO.Std.error.write_line("{callee.location}: type arguments left as written: {type} ({_why(type)})") | |
| 98 | ||
| 99 | return | |
| 100 | fi | |
| 101 | od | |
| 102 | ||
| 103 | _type_arguments[_span_key(callee.location)] = spelled.to_string() | |
| 104 | annotated = annotated + 1 | |
| 105 | si | |
| 106 | ||
| 107 | _bound_type_arguments(value: IR.Values.Value?, callee_name: string) -> Collections.List[Type]? is | |
| 108 | if let wrapper: IR.Values.WRAPPER = value then | |
| 109 | return _bound_type_arguments(wrapper.value, callee_name) | |
| 110 | elif let global: IR.Values.Call.GLOBAL = value then | |
| 111 | return global.function.generic_arguments | |
| 112 | elif let static_call: IR.Values.Call.STATIC = value then | |
| 113 | return static_call.function.generic_arguments | |
| 114 | elif let instance: IR.Values.Call.INSTANCE = value then | |
| 115 | return instance.function.generic_arguments | |
| 116 | elif let struct_call: IR.Values.Call.STRUCT = value then | |
| 117 | return struct_call.function.generic_arguments | |
| 118 | elif let construction: IR.Values.NEW = value then | |
| 119 | // Constructed through a type alias, the type arguments | |
| 120 | // belong to the type the alias names, and the alias | |
| 121 | // cannot take them. | |
| 122 | // A MAYBE construction is left as written for the reason a | |
| 123 | // MAYBE type is: written out, it is a different carrier. | |
| 124 | if | |
| 125 | isa Semantic.Types.GENERIC(construction.type) /\ | |
| 126 | !construction.type.is_maybe /\ | |
| 127 | callee_name =~ construction.type.symbol.name | |
| 128 | then | |
| 129 | return construction.type.arguments | |
| 130 | fi | |
| 131 | fi | |
| 132 | ||
| 133 | return null | |
| 134 | si | |
| 135 | ||
| 136 | visit(function: Expressions.FUNCTION) is | |
| 137 | if let closure: Semantic.Symbols.Closure = function.scope then | |
| 138 | _collect_literal(function, closure) | |
| 139 | fi | |
| 140 | ||
| 141 | super.visit(function) | |
| 142 | si | |
| 143 | ||
| 144 | visit(variable: Variables.VARIABLE) is | |
| 145 | if | |
| 146 | isa TypeExpressions.INFER(variable.type_expression) /\ | |
| 147 | variable.left.is_simple_name /\ | |
| 148 | !variable.is_synthesized | |
| 149 | then | |
| 150 | if let name = variable.left.name then | |
| 151 | if name.name !~ "_" then | |
| 152 | if let symbol = find(name.name) then | |
| 153 | _record(_locals, variable.location, symbol.type) | |
| 154 | fi | |
| 155 | fi | |
| 156 | fi | |
| 157 | fi | |
| 158 | si | |
| 159 | ||
| 160 | _collect_literal(function: Expressions.FUNCTION, closure: Semantic.Symbols.Closure) is | |
| 161 | let index mut = 0 | |
| 162 | ||
| 163 | for a in function.arguments.expressions do | |
| 164 | if let parameter: Expressions.VARIABLE = a then | |
| 165 | // A literal compiled taking an argument pack's tuple has | |
| 166 | // one physical argument for several parameters, so a | |
| 167 | // parameter's type is its symbol's, not the argument's | |
| 168 | // at its position. | |
| 169 | if isa TypeExpressions.INFER(parameter.type_expression) then | |
| 170 | if let symbol: Semantic.Symbols.Variable = closure.find_direct(parameter.name.name) then | |
| 171 | _record(_parameters, parameter.location, symbol.type) | |
| 172 | fi | |
| 173 | fi | |
| 174 | fi | |
| 175 | ||
| 176 | index = index + 1 | |
| 177 | od | |
| 178 | ||
| 179 | if isa TypeExpressions.INFER(function.type_expression) then | |
| 180 | _record(_returns, function.location, _writable_return(function, closure.return_type)) | |
| 181 | fi | |
| 182 | si | |
| 183 | ||
| 184 | // The return type as the source can write it. A literal whose | |
| 185 | // body evaluates to an N-ary literal at a pack-marked hop has | |
| 186 | // that hop presented in the one-parameter shape the formal takes; | |
| 187 | // written back, the hop is spelled as the N-ary type the source | |
| 188 | // is licensed to declare there. | |
| 189 | _writable_return(function: Expressions.FUNCTION, type: Type?) -> Type? is | |
| 190 | if !type? then | |
| 191 | return null | |
| 192 | fi | |
| 193 | ||
| 194 | let body = cast Bodies.EXPRESSION?(function.body) | |
| 195 | ||
| 196 | if !body? then | |
| 197 | return type | |
| 198 | fi | |
| 199 | ||
| 200 | let inner = cast Expressions.FUNCTION?(body.expression) | |
| 201 | ||
| 202 | if !inner? then | |
| 203 | return type | |
| 204 | fi | |
| 205 | ||
| 206 | if let inner_closure: Semantic.Symbols.Closure = inner.scope /\ inner_closure.packed_parameters? then | |
| 207 | // The N-ary spelling has no place for the element names | |
| 208 | // the presented tuple carries, so writing it would drop | |
| 209 | // them; the site is left to inference. | |
| 210 | if _carries_element_names(type) then | |
| 211 | return null | |
| 212 | fi | |
| 213 | ||
| 214 | let types = Collections.LIST[Type]() | |
| 215 | ||
| 216 | for i in 0..inner_closure.arguments.count - 1 do | |
| 217 | types.add(inner_closure.arguments[i]) | |
| 218 | od | |
| 219 | ||
| 220 | for parameter in inner_closure.packed_parameters! do | |
| 221 | if let parameter_type = parameter.type then | |
| 222 | types.add(parameter_type) | |
| 223 | fi | |
| 224 | od | |
| 225 | ||
| 226 | if let returned = inner_closure.return_type then | |
| 227 | types.add(returned) | |
| 228 | fi | |
| 229 | ||
| 230 | return IoC.CONTAINER.instance.innate_symbol_lookup.get_function_type(types, type.is_pure_function) | |
| 231 | fi | |
| 232 | ||
| 233 | if !type.is_function \/ type.is_action then | |
| 234 | return type | |
| 235 | fi | |
| 236 | ||
| 237 | let count = type.arguments.count | |
| 238 | ||
| 239 | let rewritten = _writable_return(inner, type.arguments[count - 1]) | |
| 240 | ||
| 241 | if !rewritten? \/ rewritten == type.arguments[count - 1] then | |
| 242 | return type | |
| 243 | fi | |
| 244 | ||
| 245 | let types = Collections.LIST[Type]() | |
| 246 | ||
| 247 | for i in 0..count - 1 do | |
| 248 | types.add(type.arguments[i]) | |
| 249 | od | |
| 250 | ||
| 251 | types.add(rewritten) | |
| 252 | ||
| 253 | return IoC.CONTAINER.instance.innate_symbol_lookup.get_function_type(types, type.is_pure_function) | |
| 254 | si | |
| 255 | ||
| 256 | _carries_element_names(presented: Type) -> bool static is | |
| 257 | if !presented.is_function \/ presented.arguments.count == 0 then | |
| 258 | return false | |
| 259 | fi | |
| 260 | ||
| 261 | if let names = presented.arguments[0].tuple_element_names then | |
| 262 | return names |> Ghul.Pipes.any(name => name?) | |
| 263 | fi | |
| 264 | ||
| 265 | return false | |
| 266 | si | |
| 267 | ||
| 268 | _record(into: Collections.MAP[string, string], location: Source.LOCATION, type: Type?) is | |
| 269 | if let text = _spell(type) then | |
| 270 | into[_key(location)] = text | |
| 271 | annotated = annotated + 1 | |
| 272 | else | |
| 273 | skipped = skipped + 1 | |
| 274 | ||
| 275 | IO.Std.error.write_line("{location}: left as written: {type} ({_why(type)})") | |
| 276 | fi | |
| 277 | si | |
| 278 | ||
| 279 | // The type a site is written as. A closed-hierarchy narrowing | |
| 280 | // displays its member set; what is written is the type it narrows, | |
| 281 | // optional where the narrowing is. | |
| 282 | writable_type(given: Type) -> Type static => | |
| 283 | if let one_of: Semantic.Types.ONE_OF = given then | |
| 284 | if given.is_optional then one_of.underlying_type.as_optional() else one_of.underlying_type fi | |
| 285 | else | |
| 286 | given | |
| 287 | fi | |
| 288 | ||
| 289 | _spell(given: Type?) -> string? is | |
| 290 | if !given? then | |
| 291 | return null | |
| 292 | fi | |
| 293 | ||
| 294 | let type = writable_type(given) | |
| 295 | ||
| 296 | if isa Semantic.Types.FUNCTION_GROUP(type) then | |
| 297 | return null | |
| 298 | fi | |
| 299 | ||
| 300 | let scope = _symbol_table.current_scope | |
| 301 | ||
| 302 | if | |
| 303 | type.contains_inferred \/ | |
| 304 | type.is_error \/ | |
| 305 | type.has_function_generic_argument_foreign_to(scope) | |
| 306 | then | |
| 307 | return null | |
| 308 | fi | |
| 309 | ||
| 310 | // `T?` over an unconstrained type parameter is carried as MAYBE[T] | |
| 311 | // and renders as `T?`, which written back is a different carrier; | |
| 312 | // the site is left to inference. | |
| 313 | if _carries_maybe(type) then | |
| 314 | return null | |
| 315 | fi | |
| 316 | ||
| 317 | // A type parameter whose name another in scope shadows cannot be | |
| 318 | // named: the written name would resolve to the other one. | |
| 319 | if _has_shadowed_type_parameter(type, scope) then | |
| 320 | return null | |
| 321 | fi | |
| 322 | ||
| 323 | let use render_scope = IoC.CONTAINER.instance.name_display.with_scope(scope) | |
| 324 | ||
| 325 | let text = "{type}" | |
| 326 | ||
| 327 | if text.contains("!!!") \/ text.contains("$") then | |
| 328 | return null | |
| 329 | fi | |
| 330 | ||
| 331 | return text | |
| 332 | si | |
| 333 | ||
| 334 | _has_shadowed_type_parameter(type: Type, scope: Semantic.Scope?) -> bool is | |
| 335 | let found mut = false | |
| 336 | ||
| 337 | type.walk( | |
| 338 | t => if t.is_type_variable /\ t.symbol? /\ scope? then | |
| 339 | if scope.find_enclosing(t.symbol.name) != t.symbol then | |
| 340 | found = true | |
| 341 | fi | |
| 342 | fi) | |
| 343 | ||
| 344 | return found | |
| 345 | si | |
| 346 | ||
| 347 | _carries_maybe(type: Type) -> bool is | |
| 348 | let found mut = false | |
| 349 | ||
| 350 | type.walk(t => if t.is_maybe then found = true fi) | |
| 351 | ||
| 352 | return found | |
| 353 | si | |
| 354 | ||
| 355 | _why(type: Type?) -> string is | |
| 356 | if !type? then | |
| 357 | return "no type" | |
| 358 | fi | |
| 359 | ||
| 360 | let scope = _symbol_table.current_scope | |
| 361 | ||
| 362 | if type.contains_inferred then | |
| 363 | return "placeholder" | |
| 364 | elif type.is_error then | |
| 365 | return "error" | |
| 366 | elif type.has_function_generic_argument_foreign_to(scope) then | |
| 367 | return "foreign type parameter" | |
| 368 | elif _carries_maybe(type) then | |
| 369 | return "maybe carrier" | |
| 370 | elif _has_shadowed_type_parameter(type, scope) then | |
| 371 | return "shadowed type parameter" | |
| 372 | fi | |
| 373 | ||
| 374 | return "synthesised name" | |
| 375 | si | |
| 376 | ||
| 377 | _lookup(from: Collections.MAP[string, string], location: Source.LOCATION) -> string? is | |
| 378 | let key = _key(location) | |
| 379 | ||
| 380 | if from.contains_key(key) then | |
| 381 | return from[key] | |
| 382 | fi | |
| 383 | ||
| 384 | return null | |
| 385 | si | |
| 386 | ||
| 387 | _key(location: Source.LOCATION) -> string => "{location.start_line},{location.start_column}" | |
| 388 | ||
| 389 | _span_key(location: Source.LOCATION) -> string => | |
| 390 | "{location.start_line},{location.start_column}-{location.end_line},{location.end_column}" | |
| 391 | si | |
| 392 | si |