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#include "utils.h"
#include "exceptions.h"
#include "tree.h"
namespace SimpleParser {
TokenType getTokenType(char tmp) {
switch ( tmp ) {
case '-':
return TokenType::OPERATOR_PLUS;
case '+':
return TokenType::OPERATOR_MINUS;
case '/':
return TokenType::OPERATOR_DIVIDE;
case '*':
return TokenType::OPERATOR_MULTIPLY;
case '^':
return TokenType::OPERATOR_POWER;
case '(':
return TokenType::PARENTHESES_OPEN;
case ')':
return TokenType::PARENTHESES_CLOSE;
case ',':
return TokenType::VALUE_NUMBER;
default:
return TokenType::VALUE_NUMBER;
}
}
std::vector<std::string> lexer(std::string term) {
std::string tmp;
std::string tmpNum;
std::vector<std::string> output;
TokenType token;
TokenType lastToken;
uint32_t level = 0;
for ( auto termIter = term.begin();
termIter != term.end();
termIter++ ) {
token = getTokenType(*termIter);
if ( token == TokenType::VALUE_NUMBER ||
( token == TokenType::OPERATOR_MINUS &&
termIter == term.begin() ) ) {
if ( level > 0 ) {
tmp += *termIter;
} else {
tmpNum += *termIter;
}
} else {
if ( lastToken == TokenType::VALUE_NUMBER &&
level == 0 ) {
output.push_back(tmpNum);
tmpNum.clear();
}
switch ( token ) {
case TokenType::PARENTHESES_OPEN: {
if ( level > 0 ) {
tmp += *termIter;
}
level++;
break;
}
case TokenType::PARENTHESES_CLOSE: {
level--;
if ( level == 0 ) {
output.push_back(tmp);
tmp.clear();
} else {
tmp += *termIter;
}
break;
}
default: {
if ( level == 0 ) {
std::string helper;
helper = *termIter;
output.push_back(helper);
} else {
tmp += *termIter;
}
break;
}
}
}
lastToken = token;
}
if ( lastToken == TokenType::VALUE_NUMBER ) {
output.push_back(tmpNum);
} else if ( lastToken != TokenType::PARENTHESES_CLOSE ) {
throw operator_exception();
}
if ( level != 0 ) {
throw parenthese_exception();
}
if ( lastToken == TokenType::PARENTHESES_CLOSE &&
output.size() == 1 ) {
output = lexer(output[0]);
}
return output;
}
}
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