TemplateDeduction.h revision 686775deca8b8685eb90801495880e3abdd844c2 
1//===- TemplateDeduction.h - C++ template argument deduction ----*- C++ -*-===/
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//===----------------------------------------------------------------------===/
8//
9//  This file provides types used with Sema's template argument deduction
10// routines.
11//
12//===----------------------------------------------------------------------===/
13#ifndef LLVM_CLANG_SEMA_TEMPLATE_DEDUCTION_H
14#define LLVM_CLANG_SEMA_TEMPLATE_DEDUCTION_H
15
16#include "clang/Basic/PartialDiagnostic.h"
17#include "clang/AST/DeclTemplate.h"
18#include "llvm/ADT/SmallVector.h"
19
20namespace clang {
21
22class ASTContext;
23class TemplateArgumentList;
24
25namespace sema {
26
27/// \brief Provides information about an attempted template argument
28/// deduction, whose success or failure was described by a
29/// TemplateDeductionResult value.
30class TemplateDeductionInfo {
31  /// \brief The context in which the template arguments are stored.
32  ASTContext &Context;
33
34  /// \brief The deduced template argument list.
35  ///
36  TemplateArgumentList *Deduced;
37
38  /// \brief The source location at which template argument
39  /// deduction is occurring.
40  SourceLocation Loc;
41
42  /// \brief Warnings (and follow-on notes) that were suppressed due to
43  /// SFINAE while performing template argument deduction.
44  SmallVector<PartialDiagnosticAt, 4> SuppressedDiagnostics;
45
46  // do not implement these
47  TemplateDeductionInfo(const TemplateDeductionInfo&);
48  TemplateDeductionInfo &operator=(const TemplateDeductionInfo&);
49
50public:
51  TemplateDeductionInfo(ASTContext &Context, SourceLocation Loc)
52    : Context(Context), Deduced(0), Loc(Loc) { }
53
54  ~TemplateDeductionInfo() {
55    // FIXME: if (Deduced) Deduced->Destroy(Context);
56  }
57
58  /// \brief Returns the location at which template argument is
59  /// occurring.
60  SourceLocation getLocation() const {
61    return Loc;
62  }
63
64  /// \brief Take ownership of the deduced template argument list.
65  TemplateArgumentList *take() {
66    TemplateArgumentList *Result = Deduced;
67    Deduced = 0;
68    return Result;
69  }
70
71  /// \brief Provide a new template argument list that contains the
72  /// results of template argument deduction.
73  void reset(TemplateArgumentList *NewDeduced) {
74    // FIXME: if (Deduced) Deduced->Destroy(Context);
75    Deduced = NewDeduced;
76  }
77
78  /// \brief Add a new diagnostic to the set of diagnostics
79  void addSuppressedDiagnostic(SourceLocation Loc, const PartialDiagnostic &PD) {
80    SuppressedDiagnostics.push_back(std::make_pair(Loc, PD));
81  }
82
83  /// \brief Iterator over the set of suppressed diagnostics.
84  typedef SmallVectorImpl<PartialDiagnosticAt>::const_iterator
85    diag_iterator;
86
87  /// \brief Returns an iterator at the beginning of the sequence of suppressed
88  /// diagnostics.
89  diag_iterator diag_begin() const { return SuppressedDiagnostics.begin(); }
90
91  /// \brief Returns an iterator at the end of the sequence of suppressed
92  /// diagnostics.
93  diag_iterator diag_end() const { return SuppressedDiagnostics.end(); }
94
95  /// \brief The template parameter to which a template argument
96  /// deduction failure refers.
97  ///
98  /// Depending on the result of template argument deduction, this
99  /// template parameter may have different meanings:
100  ///
101  ///   TDK_Incomplete: this is the first template parameter whose
102  ///   corresponding template argument was not deduced.
103  ///
104  ///   TDK_Inconsistent: this is the template parameter for which
105  ///   two different template argument values were deduced.
106  TemplateParameter Param;
107
108  /// \brief The first template argument to which the template
109  /// argument deduction failure refers.
110  ///
111  /// Depending on the result of the template argument deduction,
112  /// this template argument may have different meanings:
113  ///
114  ///   TDK_Inconsistent: this argument is the first value deduced
115  ///   for the corresponding template parameter.
116  ///
117  ///   TDK_SubstitutionFailure: this argument is the template
118  ///   argument we were instantiating when we encountered an error.
119  ///
120  ///   TDK_NonDeducedMismatch: this is the template argument
121  ///   provided in the source code.
122  TemplateArgument FirstArg;
123
124  /// \brief The second template argument to which the template
125  /// argument deduction failure refers.
126  ///
127  /// FIXME: Finish documenting this.
128  TemplateArgument SecondArg;
129};
130
131}
132}
133
134#endif
135