: *do 2>R ;
: DO [COMPILE] *do 0 HERE ; IMMEDIATE

: LEAVE [COMPILE] UNLOOP >R >R AHEAD R> 1+ R> ; IMMEDIATE;

ACTION-OF IS REPEAT WHILE UNTIL ELSE IF WORDS DROP 2DROP ! @ ? 2R> 2R@ 2>R >R R> R@ OVER 2OVER DUP ?DUP 2DUP SWAP 2SWAP NIP TUCK ROT -ROT PICK DEPTH 1- 1+ FALSE TRUE BRANCH (BRANCH) 0BRANCH (0BRANCH) BEGIN AGAIN THEN DO ?DO (DO) (?DO) I J UNLOOP LOOP +LOOP (+LOOP) LEAVE RECURSE ABS DABS + - * / */ */MOD UM* M* UM/MOD UD/MOD SM/REM FM/MOD MOD /MOD M+ AND OR XOR INVERT NEGATE DNEGATE MAX MIN LSHIFT RSHIFT S>D D>S D+ D- <# # #S HOLD SIGN #> U. U.R UD. . .R D. D.R 2 1 0 < = > 0= 0< COUNT >IN TYPE EMIT CHAR [CHAR] TOUPPER KEY BASE HERE PAD UNUSED MARKER ERASE FILL CELL+ CELLS CHAR+ CHARS C, C! C@ CMOVE CMOVE> MOVE ALIGN ALIGNED ALLOT , DEFER@ DEFER! DEFER ' ['] >BODY >NAME EXECUTE EVALUATE STATE COMPILE, : ; ] [ POSTPONE IMMEDIATE COMPILE-ONLY NATIVE-COMPILE CREATE DOES> (DOES>) VARIABLE 2VARIABLE TO VALUE CONSTANT +! SOURCE DECIMAL HEX BINARY DIGIT>NUMBER NUMBER >NUMBER BL CR SPACE SPACES AT-XY PAGE BOLD REGULAR BELL ." S" .( ( \ /STRING -TRAILING FIND ACCEPT PARSE PARSE-NAME WORD .S SEE DUMP (ABORT") ABORT" QUIT ABORT LITERAL (LITERAL) COLD BYE

: FACTORIAL ( n -- n! ) RECURSIVE
    DUP 1 <= IF EXIT THEN
    DUP 1 - FACTORIAL *
;