amath  1.8.5
Simple command line calculator
lexer.h
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1 /*-
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29 
30 #ifndef AMATH_LEXER_H
31 #define AMATH_LEXER_H
32 
33 /**
34  * @file lexer.h
35  * @brief Application logic tied to Lexer.
36  *
37  */
38 
39 #include "token.h"
40 
41 /**
42  * @brief Encapsulates an lexical analyzer. Provides token for the parser.
43  * @details
44  * More info on lexical analysis is available at Wikipedia:
45  * https://wikipedia.org/wiki/Lexical_analysis
46  *
47  */
48 class Lexer
49 {
50 public:
51  explicit Lexer(const char* input);
52  ~Lexer();
53 
54  void Tokenize();
55  Token* GetFirstToken() const;
56  char* GetInput() const;
57  static char* FindKeyword(Symbol symbol);
58 
59 private:
60  char* input; // Input to process by lexer
61  char* str; // Pointer to char being processed
62  unsigned int pos;
63  Token* first;
64  Token* current;
65 
66  void GetNextToken();
67  bool GetOperator();
68  bool GetQuotedIdent();
69  bool GetLiteral();
70  bool GetDigitValue();
71  static bool ShouldSkip(char character);
72  static Symbol FindKeyword(const char* ident);
73 };
74 
75 #endif
Lexer::GetOperator
bool GetOperator()
Definition: lexer.cpp:112
Lexer::ShouldSkip
static bool ShouldSkip(char character)
Definition: lexer.cpp:271
Lexer
Encapsulates an lexical analyzer. Provides token for the parser.
Definition: lexer.h:48
Lexer::GetQuotedIdent
bool GetQuotedIdent()
Definition: lexer.cpp:129
Lexer::current
Token * current
Definition: lexer.h:64
Token
Tokens are created by the Lexical Analyzer and provides an intermediate state for input consumed by t...
Definition: token.h:46
Lexer::FindKeyword
static Symbol FindKeyword(const char *ident)
Definition: lexer.cpp:243
Lexer::FindKeyword
static char * FindKeyword(Symbol symbol)
Definition: lexer.cpp:248
Lexer::~Lexer
~Lexer()
Definition: lexer.cpp:47
Lexer::input
char * input
Definition: lexer.h:60
Lexer::GetFirstToken
Token * GetFirstToken() const
Definition: lexer.cpp:62
Lexer::GetNextToken
void GetNextToken()
Definition: lexer.cpp:86
Lexer::Lexer
Lexer(const char *input)
Definition: lexer.cpp:38
Lexer::str
char * str
Definition: lexer.h:61
Lexer::pos
unsigned int pos
Definition: lexer.h:62
Lexer::GetInput
char * GetInput() const
Definition: lexer.cpp:57
Lexer::GetDigitValue
bool GetDigitValue()
Definition: lexer.cpp:216
Lexer::GetLiteral
bool GetLiteral()
Definition: lexer.cpp:166
Lexer::first
Token * first
Definition: lexer.h:63
Lexer::Tokenize
void Tokenize()
Definition: lexer.cpp:67