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parse_fmt_string now returning struct containing actual format parameters

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This commit is contained in:
Andreas Tsouchlos
2021-11-19 00:17:28 +01:00
parent f1952186e0
commit 7226241097
2 changed files with 59 additions and 30 deletions
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71
inc/parsing.h
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@@ -15,15 +15,22 @@ namespace detail {
*/
enum class FormatType { s, c, b, B, d, o, x, X, a, A, e, E, f, F, g, G, p };
template <typename result_t>
struct parse_result {
bool valid = false;
struct parse_result_t {
bool is_valid = false;
unsigned new_index = 0;
unsigned length = 0;
result_t result;
};
enum class FormatType { s, c, b, B, d, o, x, X, a, A, e, E, f, F, g, G, p };
struct fmt_string_result_t {
bool has_zero_padding = false;
int length = 6;
int precision = 2;
FormatType type = FormatType::s;
};
// clang-format off
@@ -73,7 +80,7 @@ constexpr bool is_digit(ConstString<N> s, unsigned i) {
template <std::size_t N>
constexpr parse_result<int> parse_number(ConstString<N> s, unsigned i) {
constexpr parse_result_t<int> parse_number(ConstString<N> s, unsigned i) {
int number = 0;
while ((i < s.size()) && is_digit(s, i)) {
@@ -86,7 +93,7 @@ constexpr parse_result<int> parse_number(ConstString<N> s, unsigned i) {
}
template <std::size_t N>
constexpr parse_result<FormatType> parse_type(ConstString<N> s, unsigned i) {
constexpr parse_result_t<FormatType> parse_type(ConstString<N> s, unsigned i) {
if (s[i] == 's') { // string
++i;
return {true, i, 1, FormatType::s};
@@ -99,9 +106,9 @@ constexpr parse_result<FormatType> parse_type(ConstString<N> s, unsigned i) {
} else if (s[i] == 'B') {
++i;
return {true, i, 1, FormatType::B};
// } else if (s[i] == 'c') {
// ++i;
// return {true, i, 1, FormatType::c};
// } else if (s[i] == 'c') {
// ++i;
// return {true, i, 1, FormatType::c};
} else if (s[i] == 'd') {
++i;
return {true, i, 1, FormatType::d};
@@ -143,40 +150,48 @@ constexpr parse_result<FormatType> parse_type(ConstString<N> s, unsigned i) {
return {true, i, 1, FormatType::p};
}
return {false, i, 0, FormatType::a};
return {false, i, 0, FormatType::s};
}
template <std::size_t N>
constexpr std::pair<unsigned, int> parse_fmt_string(ConstString<N> s,
unsigned i) {
int result_extra_len = 0;
constexpr parse_result_t<fmt_string_result_t> parse_fmt_string(ConstString<N> s,
unsigned i) {
if (s[i] == '0')
fmt_string_result_t result;
unsigned result_extra_len = 0;
if (s[i] == '0') {
++i;
result.has_zero_padding = true;
}
if (is_digit(s, i)) {
auto [is_valid, new_i, len, number] = parse_number(s, i);
if (!is_valid) return {i, -1};
i = new_i;
result_extra_len += number;
if (!is_valid)
return {false, i, 0, result};
i = new_i;
result.length = number;
}
if (s[i] == '.') {
++i;
auto [is_valid, new_i, len, number] = parse_number(s, i);
if (!is_valid) return {i, -1};
i = new_i;
result_extra_len += len;
if (!is_valid)
return {false, i, 0, result};
i = new_i;
result.precision = number;
}
if (s[i] != '}') {
auto [is_valid, new_i, len, type] = parse_type(s, i);
if (is_valid) return {i, -1};
i = new_i;
// result_extra_len += len;
if (!is_valid)
return {false, i, 0, result};
i = new_i;
result.type = type;
}
return {i, result_extra_len};
return {true, i, result_extra_len, result};
}
template <std::size_t N>
@@ -189,10 +204,11 @@ constexpr std::pair<unsigned, int> parse_braces(ConstString<N> s, unsigned i) {
} else if (s[i] == ':') {
++i;
auto [new_i, extra_len] = parse_fmt_string(s, i);
if (extra_len < 0) return {i, -1};
auto [is_valid, new_i, len, format_node] = parse_fmt_string(s, i);
if (!is_valid)
return {i, -1};
i = new_i;
result_extra_len += extra_len;
result_extra_len += len;
if (s[i] == '}') {
++i;
@@ -212,7 +228,8 @@ constexpr int get_output_len(ConstString<N> s) {
++i;
auto [new_i, extra_len] = parse_braces(s, i);
if (extra_len < 0) return -1;
if (extra_len < 0)
return -1;
i = new_i;
result_extra_len += extra_len;