Function patch_seq_map_has 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn patch_seq_map_has(stack: Stack) -> Stack

Check if a key exists in the map

Stack effect: ( Map key – Int )

Returns 1 if the key exists, 0 otherwise. Panics if the key type is not hashable.

Safety

Stack must have a hashable key on top and a Map below