Add an intermediate representation for the new compiler

experimental/ir/doc.go

@@ -0,0 +1,22 @@
+// Copyright 2020-2025 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 ir defines the intermediate representation used by Protocompile.
+//
+// This package provides both the IR, and the lowering machinery for that IR.
+// The IR is intended to provide a richer and easier to manipulate structure
+// compared to a FileDescriptorProto. This structure is used for name
+// resolution, type checking, tag number validation, and other semantic
+// operations.
+package ir

experimental/ir/option.go → experimental/ir/ir_option.go

@@ -46,8 +46,8 @@ type rawOption struct {
 	//
 	// In particular, (foo.bar).baz is represented as ["", "foo.bar", "baz"].
 	//
-	// The names of extensions therein are populated with fully qualified names,
-	// without the leading dot.
+	// The names of extensions therein are to be interpreted as absolute (i.e.,
+	// fully-qualified), although they will not have leading dots.
 	//
 	// If this slice is nil, that means that name resolution has not happened
 	// yet, and the ast node contains the partially-qualified extension names