# bool_overload `xs_bool_overload($pdl)` Boolean-context overload (`if $pdl`, `while $pdl`, etc.). Mirrors the `bool =>` closure in `Core.pm:838-845` of upstream PDL: - null PDL → false - multielement PDL → croak «multielement ndarray in conditional …» - bad-valued 1-elem → croak «bad value ndarray in conditional …» - 1-elem → truthiness of the single value