from-type new [ simd-element-type ] [ byte-length ] bi :> ( from-element from-length )
to-type new [ simd-element-type ] [ byte-length ] bi :> ( to-element to-length )
from-element heap-size :> from-size
from-type new [ simd-element-type ] [ byte-length ] bi :> ( from-element from-length )
to-type new [ simd-element-type ] [ byte-length ] bi :> ( to-element to-length )
from-element heap-size :> from-size