clang 8.0.0

TokenConcatenation.h
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1 //===--- TokenConcatenation.h - Token Concatenation Avoidance ---*- 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 //
10 // This file defines the TokenConcatenation class.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #ifndef LLVM_CLANG_LEX_TOKENCONCATENATION_H
15 #define LLVM_CLANG_LEX_TOKENCONCATENATION_H
16
17 #include "clang/Basic/TokenKinds.h"
18
19 namespace clang {
20 class Preprocessor;
21 class Token;
22
23 /// TokenConcatenation class, which answers the question of
24 /// "Is it safe to emit two tokens without a whitespace between them, or
25 /// would that cause implicit concatenation of the tokens?"
26 ///
27 /// For example, it emitting two identifiers "foo" and "bar" next to each
28 /// other would cause the lexer to produce one "foobar" token. Emitting "1"
29 /// and ")" next to each other is safe.
30 ///
31 class TokenConcatenation {
32 const Preprocessor &PP;
33
34 enum AvoidConcatInfo {
35 /// By default, a token never needs to avoid concatenation. Most tokens
36 /// (e.g. ',', ')', etc) don't cause a problem when concatenated.
37 aci_never_avoid_concat = 0,
38
39 /// aci_custom_firstchar - AvoidConcat contains custom code to handle this
40 /// token's requirements, and it needs to know the first character of the
41 /// token.
42 aci_custom_firstchar = 1,
43
44 /// aci_custom - AvoidConcat contains custom code to handle this token's
45 /// requirements, but it doesn't need to know the first character of the
46 /// token.
47 aci_custom = 2,
48
49 /// aci_avoid_equal - Many tokens cannot be safely followed by an '='
50 /// character. For example, "<<" turns into "<<=" when followed by an =.
51 aci_avoid_equal = 4
52 };
53
54 /// TokenInfo - This array contains information for each token on what
55 /// action to take when avoiding concatenation of tokens in the AvoidConcat
56 /// method.
57 char TokenInfo[tok::NUM_TOKENS];
58 public:
59 TokenConcatenation(const Preprocessor &PP);
60
61 bool AvoidConcat(const Token &PrevPrevTok,
62 const Token &PrevTok,
63 const Token &Tok) const;
64
65 private:
66 /// IsIdentifierStringPrefix - Return true if the spelling of the token
67 /// is literally 'L', 'u', 'U', or 'u8'.
68 bool IsIdentifierStringPrefix(const Token &Tok) const;
69 };
70 } // end clang namespace
71
72 #endif
clang::TokenConcatenation
TokenConcatenation class, which answers the question of "Is it safe to emit two tokens without a whit...
Definition: TokenConcatenation.h:31
clang::TokenConcatenation::TokenConcatenation
TokenConcatenation(const Preprocessor &PP)
Definition: TokenConcatenation.cpp:70
clang::tok::NUM_TOKENS
Definition: TokenKinds.h:28
clang::Token
Token - This structure provides full information about a lexed token.
Definition: Token.h:35
clang::format::Tok
const FormatToken & Tok
Definition: BreakableToken.h:244
clang
Dataflow Directional Tag Classes.
Definition: CFGReachabilityAnalysis.h:22
clang::TokenConcatenation::AvoidConcat
bool AvoidConcat(const Token &PrevPrevTok, const Token &PrevTok, const Token &Tok) const
AvoidConcat - If printing PrevTok immediately followed by Tok would cause the two individual tokens t...
Definition: TokenConcatenation.cpp:161
TokenKinds.h
Defines the clang::TokenKind enum and support functions.
clang::Preprocessor
Engages in a tight little dance with the lexer to efficiently preprocess tokens.
Definition: Preprocessor.h:125