wp-includes/class-wp-block-processor.php:1909Returns the span representing the currently-matched delimiter, if matched, otherwise null.
WP_HTML_Span|null public function get_span(): ?WP_HTML_Span { switch ( $this->state ) { case self::HTML_SPAN: return new WP_HTML_Span( $this->after_previous_delimiter, $this->matched_delimiter_at - $this->after_previous_delimiter ); case self::MATCHED: return new WP_HTML_Span( $this->matched_delimiter_at, $this->matched_delimiter_length ); default: return null; } }Introduced in 6.9.0. Unchanged from 6.9.7 through 7.1.0.
Signature, return type and hooks compared across 3 parsed releases.
src/wp-includes/class-wp-block-processor.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.