fork download
copy 
  1. #pragma warning(push)
  2. #pragma warning(disable: 4365)
  3. #include <vector>
  4. #include <string>
  5. #include <utility>
  6. #pragma warning(pop)
  7.  
  8. using std::string;
  9. using std::vector;
  10. using std::pair;
  11.  
  12. enum class TokenType {
  13. 	number,
  14. 	name,
  15. 	add, substract, multiply, divide, modulo,
  16. 	factorial,
  17. 	leftParenthesis, rightParenthesis,
  18. 	equal,
  19. 	statementEnding,
  20. 	quit,
  21. 	let,
  22. 	bad,
  23. 	empty
  24. };
  25.  
  26. class Token {
  27. public:
  28. 	Token(TokenType type);
  29. 	Token(TokenType type, string value);
  30.  
  31. 	double toNumeric();
  32. 	TokenType getType() const;
  33. 	string getValue() const;
  34.  
  35. 	static bool hasCharacterValue(TokenType type);
  36. 	static string tokenTypeToValue(TokenType type);
  37. 	static TokenType characterToTokenType(char ch);
  38. 	static TokenType stringToTokenType(const string& str);
  39.  
  40. private:
  41. 	TokenType type;
  42. 	string value;
  43. 	static const vector<pair<TokenType, char>> tokenTypeToCharacter_pairs;
  44. 	static const vector<pair<TokenType, string>> tokenTypeToString_pairs;
  45. };
  46.  
  47. /////////////////////////////////////////////////////////////////////////////////
  48.  
  49. //#pragma warning(push)
  50. //#pragma warning(disable: 4365)
  51. #include <string>
  52. #include <stdexcept>
  53. #include <cmath>
  54. #include <utility>
  55. #include <algorithm>
  56. #include <climits>
  57. //#pragma warning(pop)
  58.  
  59. using std::domain_error;
  60. using std::find;
  61. using std::find_if;
  62. using std::string;
  63. using std::stod;
  64. using std::numeric_limits;
  65.  
  66. Token::Token(TokenType type)
  67. 	: type{ type } {
  68. 	value = tokenTypeToValue(type);
  69. }
  70.  
  71. Token::Token(TokenType type, string value)
  72. 	: type{ type }, value{ value } {}
  73.  
  74. double Token::toNumeric() try {
  75. 	return stod(value);
  76. }
  77. catch (const std::exception&) {
  78. 	throw domain_error("\"" + value + "\" is not a real number record");
  79. }
  80.  
  81. TokenType Token::getType() const {
  82. 	return type;
  83. }
  84.  
  85. string Token::getValue() const {
  86. 	return value;
  87. }
  88.  
  89. const vector<pair<TokenType, char>> Token::tokenTypeToCharacter_pairs = {
  90. 		{TokenType::add, '+'},
  91. 		{TokenType::substract, '-'},
  92. 		{TokenType::multiply, '*'},
  93. 		{TokenType::divide, '/'},
  94. 		{TokenType::modulo, '%'},
  95. 		{TokenType::factorial, '!'},
  96. 		{TokenType::leftParenthesis, '('},
  97. 		{TokenType::rightParenthesis, ')'},
  98. 		{TokenType::equal, '='},
  99. 		{TokenType::add, '+'},
  100. 		{TokenType::statementEnding, '='}
  101. };
  102.  
  103. const vector<pair<TokenType, string>> Token::tokenTypeToString_pairs = {
  104. 	{TokenType::quit, "quit"},
  105. 	{TokenType::let, "let"},
  106. 	{TokenType::empty, "empty!"}
  107. };
  108.  
  109. bool Token::hasCharacterValue(TokenType type) {
  110. 	auto searchAmongCharactersPredicate = [type](const pair<TokenType, char>& p) -> bool {
  111. 		return p.first == type;
  112. 	};
  113. 	auto itChar = find_if(tokenTypeToCharacter_pairs.begin(), tokenTypeToCharacter_pairs.end(), searchAmongCharactersPredicate);
  114. 	return itChar != tokenTypeToCharacter_pairs.end();
  115. }
  116.  
  117. string Token::tokenTypeToValue(TokenType type) {
  118. 	auto searchAmongCharactersPredicate = [type](const pair<TokenType, char>& pair) -> bool {
  119. 		return pair.first == type;
  120. 	};
  121. 	auto itChar = find_if(tokenTypeToCharacter_pairs.begin(), tokenTypeToCharacter_pairs.end(), searchAmongCharactersPredicate);
  122. 	if (itChar != tokenTypeToCharacter_pairs.end()) {
  123. 		return string() + itChar->second;
  124. 	}
  125.  
  126. 	auto searchAmongStringsPredicate = [type](const pair<TokenType, string>& pair) -> bool {
  127. 		return pair.first == type;
  128. 	};
  129. 	auto itString = find_if(tokenTypeToString_pairs.begin(), tokenTypeToString_pairs.end(), searchAmongStringsPredicate);
  130. 	if (itString != tokenTypeToString_pairs.end()) {
  131. 		return itString->second;
  132. 	}
  133. 	throw domain_error("given token type has no definite value");
  134. }
  135.  
  136. TokenType Token::characterToTokenType(char ch) {
  137. 	auto searchPredicate =
  138. 		[ch](const pair<TokenType, char>& pair) -> bool {
  139. 		return pair.second == ch;
  140. 	};
  141. 	auto it = find_if(tokenTypeToCharacter_pairs.begin(), tokenTypeToCharacter_pairs.end(), searchPredicate);
  142. 	if (it == tokenTypeToCharacter_pairs.end()) {
  143. 		throw domain_error(string("there is not a token type that represents the character \"") + ch + "\"");
  144. 	}
  145. 	else {
  146. 		return it->first;
  147. 	}
  148. }
  149.  
  150. TokenType Token::stringToTokenType(const string& str) {
  151. 	auto searchPredicate =
  152. 		[str](const pair<TokenType, string>& p) -> bool {
  153. 		return p.second == str;
  154. 	};
  155. 	auto it = find_if(tokenTypeToString_pairs.begin(), tokenTypeToString_pairs.end(), searchPredicate);
  156. 	if (it == tokenTypeToString_pairs.end()) {
  157. 		throw domain_error(string("there is not a token type that represents the string \"") + str + "\"");
  158. 	}
  159. 	else {
  160. 		return it->first;
  161. 	}
  162. }
  163.  
  164. /////////////////////////////////////////////////////////////////////////////////
  165.  
  166. #include <iostream>
  167.  
  168. int main()
  169. {
  170. 	auto result =  Token::tokenTypeToValue(TokenType::empty);
  171.     std::cout << result; 
  172. }
Success #stdin #stdout 0.01s 5456KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
empty!
https://ideone.com/EqAmWc
language:
C++ (gcc 8.3)
created:
2 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!