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This commit is contained in:
Victor Zverovich
2024-01-14 09:16:18 -08:00
parent e420a58f24
commit 3647feaad5
2 changed files with 56 additions and 82 deletions
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67
test/scan.h
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@ -450,8 +450,7 @@ const char* parse_scan_specs(const char* begin, const char* end,
}
template <typename T, FMT_ENABLE_IF(std::is_unsigned<T>::value)>
auto read(scan_iterator it, T& value)
-> scan_iterator {
auto read(scan_iterator it, T& value) -> scan_iterator {
if (it == scan_sentinel()) return it;
char c = *it;
if (c < '0' || c > '9') throw_format_error("invalid input");
@ -484,8 +483,7 @@ auto read(scan_iterator it, T& value)
}
template <typename T, FMT_ENABLE_IF(std::is_unsigned<T>::value)>
auto read_hex(scan_iterator it, T& value)
-> scan_iterator {
auto read_hex(scan_iterator it, T& value) -> scan_iterator {
if (it == scan_sentinel()) return it;
int digit = to_hex_digit(*it);
if (digit < 0) throw_format_error("invalid input");
@ -510,13 +508,12 @@ auto read_hex(scan_iterator it, T& value)
template <typename T, FMT_ENABLE_IF(std::is_unsigned<T>::value)>
auto read(scan_iterator it, T& value, const format_specs<>& specs)
-> scan_iterator {
if (specs.type == presentation_type::hex_lower)
return read_hex(it, value);
if (specs.type == presentation_type::hex_lower) return read_hex(it, value);
return read(it, value);
}
template <typename T, FMT_ENABLE_IF(std::is_signed<T>::value)>
auto read(scan_iterator it, T& value, const format_specs<>& = {})
auto read(scan_iterator it, T& value, const format_specs<>& specs = {})
-> scan_iterator {
bool negative = it != scan_sentinel() && *it == '-';
if (negative) {
@ -525,7 +522,7 @@ auto read(scan_iterator it, T& value, const format_specs<>& = {})
}
using unsigned_type = typename std::make_unsigned<T>::type;
unsigned_type abs_value = 0;
it = read(it, abs_value);
it = read(it, abs_value, specs);
auto n = static_cast<T>(abs_value);
value = negative ? -n : n;
return it;
@ -636,6 +633,29 @@ auto make_scan_args(T&... args) -> std::array<scan_arg, sizeof...(T)> {
return {{args...}};
}
template <typename T> class scan_value {
private:
T value_;
public:
scan_value(T value) : value_(std::move(value)) {}
const T& value() const { return value_; }
};
// A rudimentary version of std::expected for testing the API shape.
template <typename T> class expected {
private:
T value_;
public:
expected(T value) : value_(std::move(value)) {}
const T* operator->() const { return &value_; }
};
template <typename T> using scan_result = expected<scan_value<T>>;
void vscan(detail::scan_buffer& buf, string_view fmt, scan_args args) {
auto h = detail::scan_handler(fmt, buf, args);
detail::parse_format_string<false>(fmt, h);
@ -650,32 +670,6 @@ auto scan_to(string_view input, string_view fmt, T&... args)
return input.begin() + (buf.begin().base() - input.data());
}
template <typename T>
class scan_value {
private:
T value_;
public:
scan_value(T value) : value_(std::move(value)) {}
const T& value() const {
return value_;
}
};
// A rudimentary version of std::expected for testing the API shape.
template <typename T>
class expected {
private:
T value_;
public:
expected(T value) : value_(std::move(value)) {}
};
template <typename T>
using scan_result = expected<scan_value<T>>;
template <typename T>
auto scan(string_view input, string_view fmt) -> scan_result<T> {
static_assert(std::is_same<remove_cvref_t<T>, T>::value, "");
@ -686,14 +680,15 @@ auto scan(string_view input, string_view fmt) -> scan_result<T> {
template <typename InputRange, typename... T,
FMT_ENABLE_IF(!std::is_convertible<InputRange, string_view>::value)>
auto scan(InputRange&& input, string_view fmt, T&... args)
auto scan_to(InputRange&& input, string_view fmt, T&... args)
-> decltype(std::begin(input)) {
auto it = std::begin(input);
vscan(get_buffer(it), fmt, make_scan_args(args...));
return it;
}
template <typename... T> bool scan(std::FILE* f, string_view fmt, T&... args) {
template <typename... T>
bool scan_to(FILE* f, string_view fmt, T&... args) {
auto&& buf = detail::file_scan_buffer(f);
vscan(buf, fmt, make_scan_args(args...));
return buf.begin() != buf.end();