// Copyright 2022 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_TINT_AST_NODE_ID_H_
#define SRC_TINT_AST_NODE_ID_H_

#include <stddef.h>

namespace tint::ast {

/// NodeID is a unique node identifier for a given Program.
/// NodeIDs are sequentially allocated, starting at 0.
struct NodeID {
    /// Equality operator
    /// @param other the other NodeID
    /// @returns true if the NodeIDs are the same
    bool operator==(NodeID other) const { return value == other.value; }

    /// Less-than comparison operator
    /// @param other the other NodeID
    /// @returns true if the other comes before this node
    bool operator<(NodeID other) const { return value < other.value; }

    /// The numerical value for the node identifier
    size_t value = 0;
};

}  // namespace tint::ast

#endif  // SRC_TINT_AST_NODE_ID_H_