( scratchpad ) \ v+v optimized. [ >R dup \ vec3 9 rot dup tag 7 eq? [ 1 slot 2dup 1 slot fixnum<= [ swap slot eq? ] [ 3drop f ] if ] [ 3drop f ] if [ ] [ \ vec3 \ v+v { vec3 vec3 } input-mismatch-error ] if 2 slot R> dup \ vec3 9 rot dup tag 7 eq? [ 1 slot 2dup 1 slot fixnum<= [ swap slot eq? ] [ 3drop f ] if ] [ 3drop f ] if [ ] [ \ vec3 \ v+v { vec3 vec3 } input-mismatch-error ] if 2 slot ( typed v+v ) { vec3 1 2 tuple 3547099654 struct 40345603621556724 vec3 127228056702 }