Here is some information about written words.

isodd ( num -- bool )

return 0 if the value is even, else 1.

isprime ( num -- addr )

return address of a cell which concains 1 if the pushed number is prime,0 otherwise.

alloc( value -- addr )

allocate 8-bit memory location and write value into that.

concat( addr addr -- addr )

return a conсatenation of 2 null terminated strings. String which address are in a top of stack will be first in the returned string.

isprimary( num -- addr )

return 1 if the pushed number is primary, else 0.