mpw/cxx/string_splitter.h
2015-02-18 12:00:21 -05:00

82 lines
1.5 KiB
C++

#ifndef __string_splitter__
#define __string_splitter__
#include <string>
class string_splitter {
public:
string_splitter(const std::string &str, char sep) :
_parent(str), _sep(sep)
{
_begin = 0;
_end = _parent.find(_sep);
_str = _parent.substr(_begin, _end);
// _begin is 0, _end is either npos or offset from 0,
// so no need to calculate a count.
}
operator bool() const {
return _begin != npos;
}
string_splitter &operator++() {
increment();
return *this;
}
const std::string &operator *() const {
return _str;
}
const std::string *operator ->() const {
return &_str;
}
private:
void increment() {
_str.clear();
if (_begin == npos) return;
if (_end == npos) { _begin = _end; return; }
_begin = _end + 1;
_end = _parent.find(_sep, _begin);
auto count = _end == npos ? _end : _end - _begin;
_str = _parent.substr(_begin, count);
}
const static auto npos = std::string::npos;
std::string _str;
const std::string &_parent;
char _sep;
std::string::size_type _begin = 0;
std::string::size_type _end = 0;
};
#ifdef TEST
#include <cstdio>
#include <cstring>
int main(int argc, char **argv)
{
if (argc != 3) {
fprintf(stderr, "Usage: %s sep string\n", argv[0]);
return 1;
}
if (strlen(argv[1]) != 1) {
fprintf(stderr, "Separator must be a single character\n");
return 1;
}
char sep = argv[1][0];
std::string str(argv[2]);
for (auto iter = string_splitter(str, sep); iter; ++iter) {
printf("%s\n", iter->c_str());
}
return 0;
}
#endif
#endif