[clang] [clang][modules] Separate parsing of modulemaps (PR #119740)

[Michael Spencer via cfe-commits]

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@@ -0,0 +1,141 @@
+//===- ModuleMapFile.h - Parsing and representation -------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_LEX_MODULEMAPFILE_H
+#define LLVM_CLANG_LEX_MODULEMAPFILE_H
+
+#include "clang/Basic/LLVM.h"
+// TODO: Consider moving ModuleId to another header, parsing a modulemap file is
+//   intended to not depend on anything about the clang::Module class.
+#include "clang/Basic/Module.h"
+#include "clang/Basic/SourceLocation.h"
+#include "llvm/ADT/StringRef.h"
+
+#include <optional>
+#include <variant>
+
+namespace clang {
+
+class DiagnosticsEngine;
+class SourceManager;
+
+namespace modulemap {
+
+using Decl =
----------------
Bigcheese wrote:

The idea was that having it in a namespace would clarify as it would only be used unqualified in the modulemap code.

https://github.com/llvm/llvm-project/pull/119740