1 //===- DeclLookups.h - Low-level interface to all names in a DC -*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 //  This file defines DeclContext::all_lookups_iterator.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_CLANG_AST_DECLLOOKUPS_H
14 #define LLVM_CLANG_AST_DECLLOOKUPS_H
15 
16 #include "clang/AST/ASTContext.h"
17 #include "clang/AST/DeclBase.h"
18 #include "clang/AST/DeclContextInternals.h"
19 #include "clang/AST/DeclarationName.h"
20 #include "clang/AST/ExternalASTSource.h"
21 #include <cstddef>
22 #include <iterator>
23 
24 namespace clang {
25 
26 /// all_lookups_iterator - An iterator that provides a view over the results
27 /// of looking up every possible name.
28 class DeclContext::all_lookups_iterator {
29   StoredDeclsMap::iterator It, End;
30 
31 public:
32   using value_type = lookup_result;
33   using reference = lookup_result;
34   using pointer = lookup_result;
35   using iterator_category = std::forward_iterator_tag;
36   using difference_type = std::ptrdiff_t;
37 
38   all_lookups_iterator() = default;
all_lookups_iterator(StoredDeclsMap::iterator It,StoredDeclsMap::iterator End)39   all_lookups_iterator(StoredDeclsMap::iterator It,
40                        StoredDeclsMap::iterator End)
41       : It(It), End(End) {}
42 
getLookupName()43   DeclarationName getLookupName() const { return It->first; }
44 
45   reference operator*() const { return It->second.getLookupResult(); }
46   pointer operator->() const { return It->second.getLookupResult(); }
47 
48   all_lookups_iterator& operator++() {
49     // Filter out using directives. They don't belong as results from name
50     // lookup anyways, except as an implementation detail. Users of the API
51     // should not expect to get them (or worse, rely on it).
52     do {
53       ++It;
54     } while (It != End &&
55              It->first == DeclarationName::getUsingDirectiveName());
56 
57     return *this;
58   }
59 
60   all_lookups_iterator operator++(int) {
61     all_lookups_iterator tmp(*this);
62     ++(*this);
63     return tmp;
64   }
65 
66   friend bool operator==(all_lookups_iterator x, all_lookups_iterator y) {
67     return x.It == y.It;
68   }
69 
70   friend bool operator!=(all_lookups_iterator x, all_lookups_iterator y) {
71     return x.It != y.It;
72   }
73 };
74 
lookups()75 inline DeclContext::lookups_range DeclContext::lookups() const {
76   DeclContext *Primary = const_cast<DeclContext*>(this)->getPrimaryContext();
77   if (Primary->hasExternalVisibleStorage())
78     getParentASTContext().getExternalSource()->completeVisibleDeclsMap(Primary);
79   if (StoredDeclsMap *Map = Primary->buildLookup())
80     return lookups_range(all_lookups_iterator(Map->begin(), Map->end()),
81                          all_lookups_iterator(Map->end(), Map->end()));
82 
83   // Synthesize an empty range. This requires that two default constructed
84   // versions of these iterators form a valid empty range.
85   return lookups_range(all_lookups_iterator(), all_lookups_iterator());
86 }
87 
88 inline DeclContext::lookups_range
noload_lookups(bool PreserveInternalState)89 DeclContext::noload_lookups(bool PreserveInternalState) const {
90   DeclContext *Primary = const_cast<DeclContext*>(this)->getPrimaryContext();
91   if (!PreserveInternalState)
92     Primary->loadLazyLocalLexicalLookups();
93   if (StoredDeclsMap *Map = Primary->getLookupPtr())
94     return lookups_range(all_lookups_iterator(Map->begin(), Map->end()),
95                          all_lookups_iterator(Map->end(), Map->end()));
96 
97   // Synthesize an empty range. This requires that two default constructed
98   // versions of these iterators form a valid empty range.
99   return lookups_range(all_lookups_iterator(), all_lookups_iterator());
100 }
101 
102 } // namespace clang
103 
104 #endif // LLVM_CLANG_AST_DECLLOOKUPS_H
105