text: // Copyright 2020 The Tint Authors.
  //
  // Licensed under the Apache License, Version 2.0 (the "License");
  // you may not use this file except in compliance with the License.
  // You may obtain a copy of the License at
  //
  //     http://www.apache.org/licenses/LICENSE-2.0
  //
  // Unless required by applicable law or agreed to in writing, software
  // distributed under the License is distributed on an "AS IS" BASIS,
  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  // See the License for the specific language governing permissions and
  // limitations under the License.
  
  #ifndef SRC_AST_IDENTIFIER_EXPRESSION_H_
  #define SRC_AST_IDENTIFIER_EXPRESSION_H_
  
  #include <memory>
  #include <utility>
  
  #include "src/ast/expression.h"
  #include "src/ast/intrinsic.h"
  #include "src/symbol.h"
  
  namespace tint {
  namespace ast {
  
  /// An identifier expression
  class IdentifierExpression : public Castable<IdentifierExpression, Expression> {
   public:
    /// Constructor
    /// @param source the source
    /// @param sym the symbol for the identifier
    IdentifierExpression(const Source& source, Symbol sym);
    /// Move constructor
    IdentifierExpression(IdentifierExpression&&);
    ~IdentifierExpression() override;
  
    /// @returns the symbol for the identifier
    Symbol symbol() const { return sym_; }
  
    /// Sets the intrinsic for this identifier
    /// @param i the intrinsic to set
    void set_intrinsic(Intrinsic i) { intrinsic_ = i; }
    /// @returns the intrinsic this identifier represents
    Intrinsic intrinsic() const { return intrinsic_; }
  
    /// Sets the intrinsic signature
    /// @param s the intrinsic signature to set
    void set_intrinsic_signature(std::unique_ptr<intrinsic::Signature> s) {
      intrinsic_sig_ = std::move(s);
    }
    /// @returns the intrinsic signature for this identifier.
    const intrinsic::Signature* intrinsic_signature() const {
      return intrinsic_sig_.get();
    }
  
    /// @returns true if this identifier is for an intrinsic
    bool IsIntrinsic() const { return intrinsic_ != Intrinsic::kNone; }
  
    /// Sets the identifier as a swizzle
    void SetIsSwizzle() { is_swizzle_ = true; }
  
    /// @returns true if this is a swizzle identifier
    bool IsSwizzle() const { return is_swizzle_; }
  
    /// Clones this node and all transitive child nodes using the `CloneContext`
    /// `ctx`.
    /// @note Semantic information such as resolved expression type and intrinsic
    /// information is not cloned.
    /// @param ctx the clone context
    /// @return the newly cloned node
    IdentifierExpression* Clone(CloneContext* ctx) const override;
  
    /// @returns true if the node is valid
    bool IsValid() const override;
  
    /// Writes a representation of the node to the output stream
    /// @param out the stream to write to
    /// @param indent number of spaces to indent the node when writing
    void to_str(std::ostream& out, size_t indent) const override;
  
   private:
    IdentifierExpression(const IdentifierExpression&) = delete;
  
    Symbol const sym_;
  
    Intrinsic intrinsic_ = Intrinsic::kNone;               // Semantic info
    std::unique_ptr<intrinsic::Signature> intrinsic_sig_;  // Semantic info
    bool is_swizzle_ = false;                              // Semantic info
  };
  
  }  // namespace ast
  }  // namespace tint
  
  #endif  // SRC_AST_IDENTIFIER_EXPRESSION_H_
  