AST: Split off ModuleNameLookup.h from NameLookup.h

include/swift/AST/ModuleNameLookup.h

@@ -0,0 +1,88 @@
+//===--- ModuleNameLookup.h - Name lookup within a module -------*- C++ -*-===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines interfaces for performing top-level name lookup into a
+// set of imported modules.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SWIFT_AST_MODULE_NAME_LOOKUP_H
+#define SWIFT_AST_MODULE_NAME_LOOKUP_H
+
+#include "llvm/ADT/SmallVector.h"
+#include "swift/AST/Identifier.h"
+#include "swift/AST/Module.h"
+#include "swift/Basic/SourceLoc.h"
+
+namespace swift {
+class ValueDecl;
+
+namespace namelookup {
+
+enum class ResolutionKind {
+  /// Lookup can match any number of decls, as long as they are all
+  /// overloadable.
+  ///
+  /// If non-overloadable decls are returned, this indicates ambiguous lookup.
+  Overloadable,
+
+  /// Lookup should match a single decl.
+  Exact,
+
+  /// Lookup should match a single decl that declares a type.
+  TypesOnly
+};
+
+/// Performs a lookup into the given module and, if necessary, its
+/// reexports, observing proper shadowing rules.
+///
+/// \param module The module that will contain the name.
+/// \param accessPath The import scope on \p module.
+/// \param name The name to look up.
+/// \param[out] decls Any found decls will be added to this vector.
+/// \param lookupKind Whether this lookup is qualified or unqualified.
+/// \param resolutionKind What sort of decl is expected.
+/// \param moduleScopeContext The top-level context from which the lookup is
+///        being performed, for checking access. This must be either a
+///        FileUnit or a Module.
+/// \param extraImports Private imports to include in this search.
+void lookupInModule(ModuleDecl *module, ModuleDecl::AccessPathTy accessPath,
+                    DeclName name, SmallVectorImpl<ValueDecl *> &decls,
+                    NLKind lookupKind, ResolutionKind resolutionKind,
+                    const DeclContext *moduleScopeContext,
+                    ArrayRef<ModuleDecl::ImportedModule> extraImports = {});
+
+template <typename Fn>
+void forAllVisibleModules(const DeclContext *DC, const Fn &fn) {
+  DeclContext *moduleScope = DC->getModuleScopeContext();
+  if (auto file = dyn_cast<FileUnit>(moduleScope))
+    file->forAllVisibleModules(fn);
+  else
+    cast<ModuleDecl>(moduleScope)
+        ->forAllVisibleModules(ModuleDecl::AccessPathTy(), fn);
+}
+
+/// Performs a qualified lookup into the given module and, if necessary, its
+/// reexports, observing proper shadowing rules.
+void
+lookupVisibleDeclsInModule(ModuleDecl *M, ModuleDecl::AccessPathTy accessPath,
+                           SmallVectorImpl<ValueDecl *> &decls,
+                           NLKind lookupKind,
+                           ResolutionKind resolutionKind,
+                           const DeclContext *moduleScopeContext,
+                           ArrayRef<ModuleDecl::ImportedModule> extraImports = {});
+
+} // end namespace namelookup
+
+} // end namespace swift
+
+#endif