| /* |
| * Copyright 2021 Google LLC. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef SKSL_DSL_FUNCTION |
| #define SKSL_DSL_FUNCTION |
| |
| #include "include/sksl/DSLBlock.h" |
| #include "include/sksl/DSLExpression.h" |
| #include "include/sksl/DSLType.h" |
| #include "include/sksl/DSLVar.h" |
| |
| namespace SkSL { |
| |
| class Block; |
| class FunctionDeclaration; |
| class Variable; |
| |
| namespace dsl { |
| |
| class DSLType; |
| |
| class DSLFunction { |
| public: |
| template<class... Parameters> |
| DSLFunction(const DSLType& returnType, const char* name, Parameters&... parameters) |
| : fReturnType(&returnType.skslType()) { |
| std::vector<DSLVar*> parameterArray; |
| parameterArray.reserve(sizeof...(parameters)); |
| |
| // in C++17, we could just do: |
| // (parameterArray.push_back(¶meters), ...); |
| int unused[] = {0, (static_cast<void>(parameterArray.push_back(¶meters)), 0)...}; |
| static_cast<void>(unused); |
| this->init(returnType, name, std::move(parameterArray)); |
| } |
| |
| virtual ~DSLFunction() = default; |
| |
| template<class... Stmt> |
| void define(Stmt... stmts) { |
| DSLBlock block = DSLBlock(DSLStatement(std::move(stmts))...); |
| this->define(std::move(block)); |
| } |
| |
| void define(DSLBlock block); |
| |
| template<class... Args> |
| DSLExpression operator()(Args&&... args) { |
| SkTArray<DSLExpression> argArray; |
| argArray.reserve_back(sizeof...(args)); |
| this->collectArgs(argArray, std::forward<Args>(args)...); |
| return this->call(std::move(argArray)); |
| } |
| |
| private: |
| void collectArgs(SkTArray<DSLExpression>& args) {} |
| |
| template<class... RemainingArgs> |
| void collectArgs(SkTArray<DSLExpression>& args, DSLVar& var, RemainingArgs&&... remaining) { |
| args.push_back(var); |
| collectArgs(args, std::forward<RemainingArgs>(remaining)...); |
| } |
| |
| template<class... RemainingArgs> |
| void collectArgs(SkTArray<DSLExpression>& args, DSLExpression expr, |
| RemainingArgs&&... remaining) { |
| args.push_back(std::move(expr)); |
| collectArgs(args, std::forward<RemainingArgs>(remaining)...); |
| } |
| |
| void init(const DSLType& returnType, const char* name, std::vector<DSLVar*> params); |
| |
| DSLExpression call(SkTArray<DSLExpression> args); |
| |
| const SkSL::Type* fReturnType; |
| const SkSL::FunctionDeclaration* fDecl; |
| }; |
| |
| } // namespace dsl |
| |
| } // namespace SkSL |
| |
| #endif |