wp-includes/template.php:632Retrieves the path of the singular template in current or parent template.
stringfunction get_singular_template() { return get_query_template( 'singular' );}Introduced in 4.3.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/template.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.