// Copyright 2020-2026 Buf Technologies, Inc.
//
// 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.

// Package id provides helpers for working with node-oriented data structures
// (such as ASTs and graphs) using compressed pointers (IDs).
//
// The whole data structure is represented by some kind of [Context] type; nodes
// of different types which that data structure are represented by [ID]s which
// index into the [Context]. The actual data of each node is stored in an
// unexported type in the package that defines it, and the exported version is
// a type based on [Node], which provides all of the helpers necessary
// for a consistent node type interface, such as IsZero, ID, and Context.
//
// [Dyn] is a variant on [ID] that is heavier but allows for storing extra
// data in addition to the ID value itself, such as type information.
package id