c++ - std::find not operating as expected -

std::find not evaluating expected.

i have vector lexeme_ defined as

static const std::string delimiters_[] = {" ", ",", "(", ")", ";", "=", ".", "*", "-"};  static std::vector<std::string> lexeme_(std::begin(delimiters_), std::end(delimiters_)); 

i have evaluation using std::find defined as

while ( std::find(lexeme_.begin(),lexeme_.end(),std::string(&commandline_.at(position_))) == lexeme_.end())              {     // concat each successive alphanumeric character 'token'     token += commandline_.at(position_);     // update index 'commandline'     position_ += 1; } 

the evaluation supposed compare char in lexeme_ char in commandline similar java expression

!lexeme.contains(character.tostring(commandline.charat(position)))   

the evaluation supposed compare chars , if determines char in delimiters satisfied in comparison, while loop exit.

testcase

#include<algorithm> #include<iostream>      static const std::string delimiters_[] = {" ", ",", "(", ")", ";", "=", ".", "*", "-"};  static std::vector<std::string> lexeme_(std::begin(delimiters_), std::end(delimiters_));  std::string commandline = "check me";  while (std::find(lexeme_.begin(),lexeme_.end(),std::string(&commandline_.at(position_))) == lexeme_.end())              {     std::cout "i should stop printing when encountering space ' ' << std::endl; } 

the constructor temporary comparison string incorrect. isn't building single-character string, it's building string starting @ character , going end of original string, if you're lucky - there might std::string implementation out there somewhere doesn't automatically 0 terminate internal buffer.

so instead of this:

std::string(&commandline_.at(position_)) 

use:

std::string(1, commandline_.at(position_))