wp-includes/rest-api.php:1523Changes a boolean-like value into the proper boolean value.
$valuebool|string|intboolfunction rest_sanitize_boolean( $value ) { // String values are translated to `true`; make sure 'false' is false. if ( is_string( $value ) ) { $value = strtolower( $value ); if ( in_array( $value, array( 'false', '0' ), true ) ) { $value = false; } } // Everything else will map nicely to boolean. return (bool) $value;}Introduced in 4.7.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/rest-api.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.