\ load a block and evaluate its content \ : source-block1 blk1-buffer blocksize ; : load ( i*x n -- j*y ) ['] source defer@ >r >in @ >r 0 >in ! buffer drop ['] source-block1 is source ['] interpret catch r> >in ! r> is source throw ; : thru ( i*x n1 n2 -- j*y ) 1+ swap ?do i load loop ;