assert_eval.hpp File Reference

Zero-width assertion evaluation (^ $ \b \B \A \Z \< \>) as free functions over a subject and a position, shared by the Pike VM and the one-pass extractor. More...

#include <cstddef>
#include <cstdint>
#include <string_view>
#include "real/core/charclass.hpp"
#include "real/core/program.hpp"
#include "real/unicode/unicode_props.hpp"
#include "real/unicode/utf8.hpp"

Include dependency graph for assert_eval.hpp:

Namespaces
namespace	real
	REAL's public API: real::regex, real::static_regex, real::flags and the match/iterator types built on them.
namespace	real::detail
	DFA construction internals: subset construction over a flattened NFA. Not a stable API.

Functions
constexpr bool	real::detail::word_before (std::string_view text, std::size_t pos, bool ascii_word)
	Word-ness of the code point ending at pos — the left side of a boundary. False at the text start or on a malformed sequence; ASCII / bytes / re.A (ascii_word) stay byte-level.
constexpr bool	real::detail::word_after (std::string_view text, std::size_t pos, bool ascii_word)
	Word-ness of the code point starting at pos — the right side of a boundary. False at the text end or on a malformed sequence; ASCII / bytes / re.A stay byte-level.
constexpr bool	real::detail::assertion_holds (assert_kind kind, std::string_view text, std::size_t pos, bool ascii_word)
	Evaluates a zero-width assertion at pos in text.

Detailed Description

Zero-width assertion evaluation (^ $ \b \B \A \Z \< \>) as free functions over a subject and a position, shared by the Pike VM and the one-pass extractor.

The multiline / trailing-newline subtleties are resolved at compile time into the real::detail::assert_kind carried by an assert_position op, so evaluation here is a pure predicate on (text, pos) plus the word-ness mode. Both callers read these functions — the Pike VM per instruction, the one-pass runtime per edge condition — so their notion of a boundary agrees by construction rather than by review.