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Iterate over a delimited input stream
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#include <iterator> | |
#include <istream> | |
#include <string> | |
#include <cassert> | |
#include <cstddef> | |
/** | |
* Iterate over each part of a delimited input stream. | |
* For example, to split a string into a vector: | |
* | |
* std::istringstream ss("This;is a;list"); | |
* std::vector<std::string> items(delim_istream_iterator<>(ss,';'), | |
* delim_istream_iterator<>()); | |
*/ | |
template <class CharT = char, | |
class Traits = std::char_traits<CharT>, | |
class Distance = std::ptrdiff_t> | |
class delim_istream_iterator | |
: public std::iterator<std::input_iterator_tag, | |
std::basic_string<CharT, Traits>, | |
Distance, | |
const std::basic_string<CharT, Traits>*, | |
const std::basic_string<CharT, Traits>&> | |
{ | |
public: | |
typedef std::basic_istream<CharT, Traits> istream_type; | |
typedef std::basic_string<CharT, Traits> value_type; | |
delim_istream_iterator() | |
: stream(nullptr), value(), ok(false) { } | |
delim_istream_iterator(istream_type& stream, CharT delimiter) | |
: stream(&stream), delimiter(delimiter) { | |
read(); | |
} | |
delim_istream_iterator(const delim_istream_iterator& other) | |
: stream(other.stream), value(other.value), | |
ok(other.ok), delimiter(other.delimiter) { } | |
value_type operator*() const { | |
assert(ok); | |
return value; | |
} | |
const value_type* operator->() const { | |
return &(operator*()); | |
} | |
delim_istream_iterator& operator++() { | |
assert(ok); | |
read(); | |
return *this; | |
} | |
delim_istream_iterator operator++(int) { | |
assert(ok); | |
delim_istream_iterator temp = *this; | |
read(); | |
return temp; | |
} | |
friend bool operator==(const delim_istream_iterator& a, | |
const delim_istream_iterator& b) { | |
return (a.ok == b.ok) && (!a.ok || a.stream == b.stream); | |
} | |
friend bool operator!=(const delim_istream_iterator& a, | |
const delim_istream_iterator& b) { | |
return !operator==(a, b); | |
} | |
private: | |
istream_type* stream; | |
value_type value; | |
bool ok; | |
CharT delimiter; | |
void read() { | |
ok = (stream && *stream); | |
if (ok) { | |
std::getline(*stream, value, delimiter); | |
ok = *stream; | |
} | |
} | |
}; |
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There are a bug at line 47: returning address of temporary local variable.