text.cpp
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#include "crucible/parsing/text.hpp"
#include <sstream>
namespace crucible::parsing::text {
TextState::TextState(std::u8string_view const &input) :
my_input(input) {
}
TextState::TextState(std::u8string_view const &input, std::size_t const code_unit_offset) :
my_input(input),
my_code_unit_offset(code_unit_offset) {
}
auto TextState::is_finished() const -> bool {
return my_code_unit_offset >= my_input.size();
}
auto TextState::get_remaining_code_units_in_input() const -> std::u8string_view {
return my_input.substr(my_code_unit_offset);
}
auto TextState::advance_by_code_units(std::size_t const code_unit_count) const -> TextState {
return TextState { my_input, my_code_unit_offset + code_unit_count };
}
auto TextState::format_location() const -> std::string {
std::ostringstream buffer;
buffer
<< "{ \"source_type\" : \"text\", \"code_unit\" : "
<< my_code_unit_offset
<< " }";
return buffer.str();
}
CharacterSequence::CharacterSequence(std::u8string_view const &character_sequence) :
my_character_sequence(character_sequence) {
}
auto CharacterSequence::operator()(StateType const &state) const -> ResultType {
auto const &remaining_code_units = state.get_remaining_code_units_in_input();
if (remaining_code_units.size() < my_character_sequence.size()) {
return result::reject(state, TextError { CharacterSequenceMismatch {} });
}
auto const sequence_begin = my_character_sequence.begin();
auto const sequence_end = my_character_sequence.end();
auto const input_begin = remaining_code_units.begin();
bool const is_equal = std::equal(sequence_begin, sequence_end, input_begin);
if (is_equal) {
auto const next_state = state.advance_by_code_units(my_character_sequence.size());
return result::accept(next_state, core::none::None {});
} else {
return result::reject(state, TextError { CharacterSequenceMismatch {} });
}
}
}