 A fully featured Forth system with all source code will compile itself , a technique commonly called meta @-@ compilation by Forth programmers ( although the term doesn 't exactly match meta @-@ compilation as it is normally defined ) . The usual method is to redefine the handful of words that place compiled bits into memory . The compiler 's words use specially named versions of fetch and store that can be redirected to a buffer area in memory . The buffer area simulates or accesses a memory area beginning at a different address than the code buffer . Such compilers define words to access both the target computer 's memory , and the host ( compiling ) computer 's memory . 
