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Merged
Stephan T. Lavavej (StephanTLavavej) merged 5 commits into from
Aug 16, 2025
Merged

<regex>: Compare against char directly #5675

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0c958d7
` == static_cast<_Elem>\(static_cast<char>\((\w+)\)\)` => ` == static…
StephanTLavavej Aug 12, 2025
5fd081c
` == static_cast<_Elem>\(('\w')\)` => ` == $1`
StephanTLavavej Aug 12, 2025
47351a2
Support heterogeneous comparisons with char.
StephanTLavavej Aug 13, 2025
0c47754
Centralize operators with more cromulent casts.
StephanTLavavej Aug 13, 2025
5188084
Merge branch 'main' into regex-char-comparisons
StephanTLavavej Aug 16, 2025
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54 changes: 23 additions & 31 deletions stl/inc/regex
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Original file line number Diff line number Diff line change
Expand Up @@ -4367,11 +4367,9 @@ template <class _FwdIt, class _Elem, class _RxTraits>
bool _Parser2<_FwdIt, _Elem, _RxTraits>::_Is_esc(_FwdIt _Ch0) const { // assumes _Ch0 != _End
return _Mode == _Lex_mode::_Default && ++_Ch0 != _End
&& ((!(_L_flags & _L_nex_grp)
&& (*_Ch0 == static_cast<_Elem>(static_cast<char>(_Meta_lpar))
|| *_Ch0 == static_cast<_Elem>(static_cast<char>(_Meta_rpar))))
&& (*_Ch0 == static_cast<char>(_Meta_lpar) || *_Ch0 == static_cast<char>(_Meta_rpar)))
|| (!(_L_flags & _L_nex_rep)
&& (*_Ch0 == static_cast<_Elem>(static_cast<char>(_Meta_lbr))
|| *_Ch0 == static_cast<_Elem>(static_cast<char>(_Meta_rbr)))));
&& (*_Ch0 == static_cast<char>(_Meta_lbr) || *_Ch0 == static_cast<char>(_Meta_rbr))));
}

template <class _FwdIt, class _Elem, class _RxTraits>
Expand Down Expand Up @@ -4442,7 +4440,7 @@ void _Parser2<_FwdIt, _Elem, _RxTraits>::_Trans() { // map character to meta-cha
{ // check if $ is special
_FwdIt _Next = _Pat;
if ((_L_flags & _L_anch_rstr) && ++_Next != _End) {
const bool _Escaped = *_Next == static_cast<_Elem>(static_cast<char>(_Meta_esc)) && _Is_esc(_Next);
const bool _Escaped = *_Next == static_cast<char>(_Meta_esc) && _Is_esc(_Next);
if (_Escaped) {
++_Next;
}
Expand All @@ -4454,9 +4452,9 @@ void _Parser2<_FwdIt, _Elem, _RxTraits>::_Trans() { // map character to meta-cha

const _Elem _Ch = *_Next;
const bool _Is_end_of_alternative =
((_L_flags & _L_alt_nl) && _Ch == static_cast<_Elem>(static_cast<char>(_Meta_nl))
((_L_flags & _L_alt_nl) && _Ch == static_cast<char>(_Meta_nl)
&& _Disj_count == 0) // dollar followed by newline '\n' for alternation
|| (_Escaped && _Ch == static_cast<_Elem>(static_cast<char>(_Meta_rpar))
|| (_Escaped && _Ch == static_cast<char>(_Meta_rpar)
&& _Disj_count != 0); // dollar followed by (escaped) right parenthesis ')' closing a group

if (!_Is_end_of_alternative) {
Expand Down Expand Up @@ -4490,7 +4488,7 @@ void _Parser2<_FwdIt, _Elem, _RxTraits>::_Trans() { // map character to meta-cha
template <class _FwdIt, class _Elem, class _RxTraits>
void _Parser2<_FwdIt, _Elem, _RxTraits>::_Next() { // advance to next input character
if (_Pat != _End) { // advance
if (*_Pat == static_cast<_Elem>(static_cast<char>(_Meta_esc)) && _Is_esc(_Pat)) {
if (*_Pat == static_cast<char>(_Meta_esc) && _Is_esc(_Pat)) {
++_Pat;
}

Expand Down Expand Up @@ -4621,10 +4619,10 @@ bool _Parser2<_FwdIt, _Elem, _RxTraits>::_CharacterClassEscape(bool _Addit) { //
return false;
}

auto _Kind = (_Char == static_cast<_Elem>('W') ? _Rx_char_class_kind::_Negated_w
: _Char == static_cast<_Elem>('S') ? _Rx_char_class_kind::_Negated_s
: _Char == static_cast<_Elem>('D') ? _Rx_char_class_kind::_Negated_d
: _Rx_char_class_kind::_Positive);
auto _Kind = (_Char == 'W' ? _Rx_char_class_kind::_Negated_w
: _Char == 'S' ? _Rx_char_class_kind::_Negated_s
: _Char == 'D' ? _Rx_char_class_kind::_Negated_d
: _Rx_char_class_kind::_Positive);

if (_Addit) {
_Nfa._Add_class();
Expand All @@ -4644,8 +4642,7 @@ bool _Parser2<_FwdIt, _Elem, _RxTraits>::_CharacterClassEscape(bool _Addit) { //

template <class _FwdIt, class _Elem, class _RxTraits>
_Prs_ret _Parser2<_FwdIt, _Elem, _RxTraits>::_ClassEscape() { // check for class escape
if ((_L_flags & _L_esc_bsp)
&& _Char == static_cast<_Elem>(static_cast<char>(_Esc_ctrl_b))) { // handle backspace escape
if ((_L_flags & _L_esc_bsp) && _Char == static_cast<char>(_Esc_ctrl_b)) { // handle backspace escape
_Next();
_Unescaped_char = static_cast<_Elem>(static_cast<char>(_Meta_bsp));
return _Prs_chr;
Expand Down Expand Up @@ -4894,15 +4891,15 @@ bool _Parser2<_FwdIt, _Elem, _RxTraits>::_IdentityEscape(bool _In_character_clas

template <class _FwdIt, class _Elem, class _RxTraits>
bool _Parser2<_FwdIt, _Elem, _RxTraits>::_Do_ffn(_Elem _Ch) { // check for limited file format escape characters
if (_Ch == static_cast<_Elem>(static_cast<char>(_Esc_ctrl_f))) {
if (_Ch == static_cast<char>(_Esc_ctrl_f)) {
_Val = '\f';
} else if (_Ch == static_cast<_Elem>(static_cast<char>(_Esc_ctrl_n))) {
} else if (_Ch == static_cast<char>(_Esc_ctrl_n)) {
_Val = '\n';
} else if (_Ch == static_cast<_Elem>(static_cast<char>(_Esc_ctrl_r))) {
} else if (_Ch == static_cast<char>(_Esc_ctrl_r)) {
_Val = '\r';
} else if (_Ch == static_cast<_Elem>(static_cast<char>(_Esc_ctrl_t))) {
} else if (_Ch == static_cast<char>(_Esc_ctrl_t)) {
_Val = '\t';
} else if (_Ch == static_cast<_Elem>(static_cast<char>(_Esc_ctrl_v))) {
} else if (_Ch == static_cast<char>(_Esc_ctrl_v)) {
_Val = '\v';
} else {
return false;
Expand All @@ -4913,9 +4910,9 @@ bool _Parser2<_FwdIt, _Elem, _RxTraits>::_Do_ffn(_Elem _Ch) { // check for limit

template <class _FwdIt, class _Elem, class _RxTraits>
bool _Parser2<_FwdIt, _Elem, _RxTraits>::_Do_ffnx(_Elem _Ch) { // check for the remaining file format escape characters
if (_Ch == static_cast<_Elem>(static_cast<char>(_Esc_ctrl_a))) {
if (_Ch == static_cast<char>(_Esc_ctrl_a)) {
_Val = '\a';
} else if (_Ch == static_cast<_Elem>(static_cast<char>(_Esc_ctrl_b))) {
} else if (_Ch == static_cast<char>(_Esc_ctrl_b)) {
_Val = '\b';
} else {
return false;
Expand All @@ -4933,8 +4930,7 @@ bool _Parser2<_FwdIt, _Elem, _RxTraits>::_CharacterEscape(bool _In_character_cla

if ((_L_flags & _L_esc_ffn && _Do_ffn(_Char)) || (_L_flags & _L_esc_ffnx && _Do_ffnx(_Char))) {
_Next();
} else if (_Char == static_cast<_Elem>(static_cast<char>(_Esc_ctrl))
&& (_L_flags & _L_esc_ctrl)) { // handle control escape sequence
} else if (_Char == static_cast<char>(_Esc_ctrl) && (_L_flags & _L_esc_ctrl)) { // handle control escape sequence
_Next();

using _Char_traits_type = typename _RxTraits::string_type::traits_type;
Expand All @@ -4947,12 +4943,10 @@ bool _Parser2<_FwdIt, _Elem, _RxTraits>::_CharacterEscape(bool _In_character_cla

_Val = static_cast<unsigned char>(_Char) % 32;
_Next();
} else if (_Char == static_cast<_Elem>(static_cast<char>(_Esc_hex))
&& (_L_flags & _L_esc_hex)) { // handle hexadecimal escape sequence
} else if (_Char == static_cast<char>(_Esc_hex) && (_L_flags & _L_esc_hex)) { // handle hexadecimal escape sequence
_Next();
_HexDigits(2);
} else if (_Char == static_cast<_Elem>(static_cast<char>(_Esc_uni))
&& (_L_flags & _L_esc_uni)) { // handle Unicode escape sequence
} else if (_Char == static_cast<char>(_Esc_uni) && (_L_flags & _L_esc_uni)) { // handle Unicode escape sequence
_Next();
_HexDigits(4);
} else if ((_L_flags & _L_esc_oct) && _OctalDigits()) { // handle octal escape sequence
Expand Down Expand Up @@ -5068,13 +5062,11 @@ bool _Parser2<_FwdIt, _Elem, _RxTraits>::_Alternative() { // check for valid alt
_Next();
} else if (_Mchar == _Meta_esc) { // check for valid escape sequence
_Next();
if ((_L_flags & _L_asrt_wrd)
&& _Char == static_cast<_Elem>(static_cast<char>(_Esc_word))) { // add word assert
if ((_L_flags & _L_asrt_wrd) && _Char == static_cast<char>(_Esc_word)) { // add word assert
_Nfa._Add_wbound();
_Next();
_Quant = false;
} else if ((_L_flags & _L_asrt_wrd)
&& _Char == static_cast<_Elem>(static_cast<char>(_Esc_not_word))) { // add not-word assert
} else if ((_L_flags & _L_asrt_wrd) && _Char == static_cast<char>(_Esc_not_word)) { // add not-word assert
_Nfa._Add_wbound();
_Nfa._Negate();
_Next();
Expand Down
76 changes: 69 additions & 7 deletions tests/std/tests/GH_000995_regex_custom_char_types/test.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -13,8 +13,53 @@

using namespace std;

enum class signed_wchar_enum : short {};
enum class ullong_enum : unsigned long long {};
namespace signed_wchar_ns {
enum class signed_wchar_enum : short {};

bool operator==(const signed_wchar_enum swe, const char ch) {
return static_cast<unsigned short>(swe) == static_cast<unsigned char>(ch);
}

#if !_HAS_CXX20
bool operator!=(const signed_wchar_enum swe, const char ch) {
return !(swe == ch);
}

bool operator==(const char ch, const signed_wchar_enum swe) {
return swe == ch;
}

bool operator!=(const char ch, const signed_wchar_enum swe) {
return !(swe == ch);
}
#endif // !_HAS_CXX20
} // namespace signed_wchar_ns

using signed_wchar_ns::signed_wchar_enum;

namespace ullong_ns {
enum class ullong_enum : unsigned long long {};

bool operator==(const ullong_enum ull, const char ch) {
return static_cast<unsigned long long>(ull) == static_cast<unsigned char>(ch);
}

#if !_HAS_CXX20
bool operator!=(const ullong_enum ull, const char ch) {
return !(ull == ch);
}

bool operator==(const char ch, const ullong_enum ull) {
return ull == ch;
}

bool operator!=(const char ch, const ullong_enum ull) {
return !(ull == ch);
}
#endif // !_HAS_CXX20
} // namespace ullong_ns

using ullong_ns::ullong_enum;

template <class T>
T convert_to(const signed_wchar_enum& char_enum) {
Expand Down Expand Up @@ -55,6 +100,28 @@ class wrapped_character {
return lhs.character == rhs.character;
}

friend bool operator==(const wrapped_character& wc, const char ch) {
return wc.character == static_cast<Elem>(ch);
}

#if !_HAS_CXX20
friend bool operator!=(const wrapped_character& lhs, const wrapped_character& rhs) {
return !(lhs == rhs);
}

friend bool operator!=(const wrapped_character& wc, const char ch) {
return !(wc == ch);
}

friend bool operator==(const char ch, const wrapped_character& wc) {
return wc == ch;
}

friend bool operator!=(const char ch, const wrapped_character& wc) {
return !(wc == ch);
}
#endif // !_HAS_CXX20

template <class T>
friend T convert_to(const wrapped_character<Elem>& wrapped_char) {
return static_cast<T>(wrapped_char.character);
Expand All @@ -67,11 +134,6 @@ class wrapped_character {
template <class T, class Elem>
T convert_to(const wrapped_character<Elem>& wrapped_char);

template <class Elem>
bool operator!=(const wrapped_character<Elem>& lhs, const wrapped_character<Elem>& rhs) {
return !(lhs == rhs);
}

using wrapped_wchar = wrapped_character<wchar_t>;
using wrapped_ullong = wrapped_character<unsigned long long>;

Expand Down