Files
carbon-lang/executable_semantics/interpreter/exec_program.cpp
T
Geoff Romer d854fb93cb Factor out AST node for function return types. (#912)
This enables us to stop treating the return type as a Pattern (which is really isn't), treat return types more consistently with other static types in the typechecker, and drop ReturnTypeContext.

Additional changes:
- Merge TypeCheckFunDef with TypeOfFunDef.
- Handle implicit conversions in `return` statements.
- Require function type literals to have an explicit `->`.
- Move consistency check for omitted returns from TypeChecker to ResolveControlFlow.
2021-11-12 11:30:31 -08:00

72 lines
2.9 KiB
C++

// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
// Exceptions. See /LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "executable_semantics/interpreter/exec_program.h"
#include "common/check.h"
#include "common/ostream.h"
#include "executable_semantics/common/arena.h"
#include "executable_semantics/interpreter/interpreter.h"
#include "executable_semantics/interpreter/resolve_control_flow.h"
#include "executable_semantics/interpreter/resolve_names.h"
#include "executable_semantics/interpreter/type_checker.h"
namespace Carbon {
// Adds builtins, currently only Print(). Note Print() is experimental, not
// standardized, but is made available for printing state in tests.
static void AddIntrinsics(Nonnull<Arena*> arena,
std::vector<Nonnull<Declaration*>>* declarations) {
SourceLocation source_loc("<intrinsic>", 0);
std::vector<Nonnull<Pattern*>> print_params = {arena->New<BindingPattern>(
source_loc, "format_str",
arena->New<ExpressionPattern>(
arena->New<StringTypeLiteral>(source_loc)))};
auto print_return = arena->New<Block>(
source_loc, std::vector<Nonnull<Statement*>>({arena->New<Return>(
source_loc,
arena->New<IntrinsicExpression>(
IntrinsicExpression::Intrinsic::Print),
false)}));
auto print = arena->New<FunctionDeclaration>(
source_loc, "Print", std::vector<Nonnull<GenericBinding*>>(),
arena->New<TuplePattern>(source_loc, print_params),
ReturnTerm::Explicit(arena->New<TupleLiteral>(source_loc)), print_return);
declarations->insert(declarations->begin(), print);
}
void ExecProgram(Nonnull<Arena*> arena, AST ast, bool trace) {
AddIntrinsics(arena, &ast.declarations);
if (trace) {
llvm::outs() << "********** source program **********\n";
for (const auto decl : ast.declarations) {
llvm::outs() << *decl;
}
llvm::outs() << "********** type checking **********\n";
}
// Although name resolution is currently done once, generic programming
// (particularly templates) may require more passes.
ResolveNames(arena, ast);
ResolveControlFlow(ast);
TypeChecker(arena, trace).TypeCheck(ast);
if (trace) {
llvm::outs() << "\n";
llvm::outs() << "********** type checking complete **********\n";
for (const auto decl : ast.declarations) {
llvm::outs() << *decl;
}
llvm::outs() << "********** starting execution **********\n";
}
SourceLocation source_loc("<Main()>", 0);
Nonnull<Expression*> call_main = arena->New<CallExpression>(
source_loc, arena->New<IdentifierExpression>(source_loc, "Main"),
arena->New<TupleLiteral>(source_loc));
int result =
Interpreter(arena, trace).InterpProgram(ast.declarations, call_main);
llvm::outs() << "result: " << result << "\n";
}
} // namespace Carbon