+QDUP = defPrim("?DUP", () -> begin
+ ensurePSDepth(1)
+ val = mem[reg.PSP]
+ if val != 0
+ pushPS(val)
+ end
+ return mem[NEXT]
+end)
+
+INCR = defPrim("1+", () -> begin
+ ensurePSDepth(1)
+ mem[reg.PSP] += 1
+ return mem[NEXT]
+end)
+
+DECR = defPrim("1-", () -> begin
+ ensurePSDepth(1)
+ mem[reg.PSP] -= 1
+ return mem[NEXT]
+end)
+
+INCR2 = defPrim("2+", () -> begin
+ ensurePSDepth(1)
+ mem[reg.PSP] += 2
+ return mem[NEXT]
+end)
+
+DECR2 = defPrim("2-", () -> begin
+ ensurePSDepth(1)
+ mem[reg.PSP] -= 2
+ return mem[NEXT]
+end)
+
+ADD = defPrim("+", () -> begin
+ b = popPS()
+ a = popPS()
+ pushPS(a+b)
+ return mem[NEXT]
+end)
+
+SUB = defPrim("-", () -> begin
+ b = popPS()
+ a = popPS()
+ pushPS(a-b)
+ return mem[NEXT]
+end)
+
+MUL = defPrim("*", () -> begin
+ b = popPS()
+ a = popPS()
+ pushPS(a*b)
+ return mem[NEXT]
+end)
+
+DIVMOD = defPrim("/MOD", () -> begin
+ b = popPS()
+ a = popPS()
+ q,r = divrem(a,b)
+ pushPS(r)
+ pushPS(q)
+ return mem[NEXT]
+end)
+
+EQU = defPrim("=", () -> begin
+ b = popPS()
+ a = popPS()
+ pushPS(a==b ? -1 : 0)
+ return mem[NEXT]
+end)
+
+NEQU = defPrim("<>", () -> begin
+ b = popPS()
+ a = popPS()
+ pushPS(a!=b ? -1 : 0)
+ return mem[NEXT]
+end)
+
+LT = defPrim("<", () -> begin
+ b = popPS()
+ a = popPS()
+ pushPS(a<b ? -1 : 0)
+ return mem[NEXT]
+end)
+
+GT = defPrim(">", () -> begin
+ b = popPS()
+ a = popPS()
+ pushPS(a>b ? -1 : 0)
+ return mem[NEXT]
+end)
+
+LE = defPrim("<=", () -> begin
+ b = popPS()
+ a = popPS()
+ pushPS(a<=b ? -1 : 0)
+ return mem[NEXT]
+end)
+
+GE = defPrim(">=", () -> begin
+ b = popPS()
+ a = popPS()
+ pushPS(a>=b ? -1 : 0)
+ return mem[NEXT]
+end)
+
+ZEQU = defPrim("0=", () -> begin
+ pushPS(popPS() == 0 ? -1 : 0)
+ return mem[NEXT]
+end)
+
+ZNEQU = defPrim("0<>", () -> begin
+ pushPS(popPS() != 0 ? -1 : 0)
+ return mem[NEXT]
+end)
+
+ZLT = defPrim("0<", () -> begin
+ pushPS(popPS() < 0 ? -1 : 0)
+ return mem[NEXT]
+end)
+
+ZGT = defPrim("0>", () -> begin
+ pushPS(popPS() > 0 ? -1 : 0)
+ return mem[NEXT]
+end)
+
+ZLE = defPrim("0<=", () -> begin
+ pushPS(popPS() <= 0 ? -1 : 0)
+ return mem[NEXT]
+end)
+
+ZGE = defPrim("0>=", () -> begin
+ pushPS(popPS() >= 0 ? -1 : 0)
+ return mem[NEXT]
+end)
+
+AND = defPrim("AND", () -> begin
+ b = popPS()
+ a = popPS()
+ pushPS(a & b)
+ return mem[NEXT]
+end)
+
+OR = defPrim("OR", () -> begin
+ b = popPS()
+ a = popPS()
+ pushPS(a | b)
+ return mem[NEXT]
+end)
+
+XOR = defPrim("XOR", () -> begin
+ b = popPS()
+ a = popPS()
+ pushPS(a $ b)
+ return mem[NEXT]
+end)
+
+INVERT = defPrim("INVERT", () -> begin
+ pushPS(~popPS())
+ return mem[NEXT]
+end)
+
+# Literals
+
+LIT = defPrim("LIT", () -> begin
+ pushPS(mem[reg.IP])
+ reg.IP += 1
+ return mem[NEXT]
+end)
+
+# Memory primitives
+
+STORE = defPrim("!", () -> begin
+ addr = popPS()
+ dat = popPS()
+ mem[addr] = dat
+ return mem[NEXT]
+end)
+
+FETCH = defPrim("@", () -> begin
+ addr = popPS()
+ pushPS(mem[addr])
+ return mem[NEXT]
+end)
+
+ADDSTORE = defPrim("+!", () -> begin
+ addr = popPS()
+ toAdd = popPS()
+ mem[addr] += toAdd
+ return mem[NEXT]
+end)
+
+SUBSTORE = defPrim("-!", () -> begin
+ addr = popPS()
+ toSub = popPS()
+ mem[addr] -= toSub
+ return mem[NEXT]
+end)
+
+
+# Built-in variables
+
+HERE_CFA = defExistingVar("HERE", HERE)
+LATEST_CFA = defExistingVar("LATEST", LATEST)
+PSP0_CFA = defExistingVar("PSP0", PSP0)
+RSP0_CFA = defExistingVar("RSP0", RSP0)
+STATE, STATE_CFA = defNewVar("STATE", 0)
+BASE, BASE_CFA = defNewVar("BASE", 10)
+
+# Constants
+
+defConst("VERSION", 1)
+defConst("DOCOL", DOCOL)
+defConst("DICT", DICT)
+F_IMMED = defConst("F_IMMED", 128)
+F_HIDDEN = defConst("F_HIDDEN", 256)
+F_LENMASK = defConst("F_LENMASK", 127)
+
+# Return Stack
+
+TOR = defPrim(">R", () -> begin
+ pushRS(popPS())
+ return mem[NEXT]
+end)
+
+FROMR = defPrim("R>", () -> begin
+ pushPS(popRS())
+ return mem[NEXT]
+end)
+
+RSPFETCH = defPrim("RSP@", () -> begin
+ pushPS(reg.RSP)
+ return mem[NEXT]
+end)
+
+RSPSTORE = defPrim("RSP!", () -> begin
+ RSP = popPS()
+ return mem[NEXT]
+end)
+
+RDROP = defPrim("RDROP", () -> begin
+ popRS()
+ return mem[NEXT]
+end)
+
+# Parameter Stack
+
+PSPFETCH = defPrim("PSP@", () -> begin
+ pushPS(reg.PSP)
+ return mem[NEXT]
+end)
+
+PSPSTORE = defPrim("PSP!", () -> begin
+ PSP = popPS()
+ return mem[NEXT]
+end)
+
+# I/O
+
+defConst("TIB", TIB)
+NUMTIB, NUMTIB_CFA = defNewVar("#TIB", 0)
+TOIN, TOIN_CFA = defNewVar(">IN", 0)
+
+KEY = defPrim("KEY", () -> begin
+ if mem[TOIN] >= mem[NUMTIB]
+ mem[TOIN] = 0
+ line = readline()
+ mem[NUMTIB] = length(line)
+ putString(line, TIB)
+ end
+
+ pushPS(mem[TIB + mem[TOIN]])
+ mem[TOIN] += 1
+
+ return mem[NEXT]
+end)
+
+EMIT = defPrim("EMIT", () -> begin
+ print(Char(popPS()))
+ return mem[NEXT]
+end)
+
+WORD = defPrim("WORD", () -> begin
+
+ c = -1
+
+ skip_to_end = false
+ while true
+
+ callPrim(mem[KEY])
+ c = Char(popPS())
+
+ if c == '\\'
+ skip_to_end = true
+ continue
+ end
+
+ if skip_to_end
+ if c == '\n'
+ skip_to_end = false
+ end
+ continue
+ end
+
+ if c == ' ' || c == '\t'
+ continue
+ end
+
+ break
+ end
+
+ wordAddr = mem[HERE]
+ offset = 0
+
+ if c == '\n'
+ # Treat newline as a special word
+
+ mem[wordAddr + offset] = Int64(c)
+ pushPS(wordAddr)
+ pushPS(1)
+ return mem[NEXT]
+ end
+
+ while true
+ mem[wordAddr + offset] = Int64(c)
+ offset += 1
+
+ callPrim(mem[KEY])
+ c = Char(popPS())
+
+ if c == ' ' || c == '\t' || c == '\n'
+ # Rewind KEY
+ mem[TOIN] -= 1
+ break
+ end
+ end
+
+ wordLen = offset
+
+ pushPS(wordAddr)
+ pushPS(wordLen)
+
+ return mem[NEXT]
+end)
+
+NUMBER = defPrim("NUMBER", () -> begin
+
+ wordLen = popPS()
+ wordAddr = popPS()
+
+ s = getString(wordAddr, wordLen)
+
+ try
+ pushPS(parse(Int64, s, mem[BASE]))
+ pushPS(0)
+ catch
+ pushPS(1) # Error indication
+ end
+
+ return mem[NEXT]
+end)
+
+# Dictionary searches
+
+FIND = defPrim("FIND", () -> begin
+
+ wordLen = popPS()
+ wordAddr = popPS()
+ word = lowercase(getString(wordAddr, wordLen))
+
+ latest = LATEST
+
+ i = 0
+ while (latest = mem[latest]) > 0
+ lenAndFlags = mem[latest+1]
+ len = lenAndFlags & F_LENMASK
+ hidden = (lenAndFlags & F_HIDDEN) == F_HIDDEN
+
+ if hidden || len != wordLen
+ continue
+ end
+
+ thisAddr = latest+2
+ thisWord = lowercase(getString(thisAddr, len))
+
+ if lowercase(thisWord) == lowercase(word)
+ break
+ end
+ end
+
+ pushPS(latest)
+
+ return mem[NEXT]
+end)
+
+TOCFA = defPrim(">CFA", () -> begin
+
+ addr = popPS()
+ lenAndFlags = mem[addr+1]
+ len = lenAndFlags & F_LENMASK
+
+ pushPS(addr + 2 + len)
+
+ return mem[NEXT]
+end)
+
+TODFA = defWord(">DFA", [TOCFA, INCR, EXIT])
+
+# Compilation
+
+CREATE = defPrim("CREATE", () -> begin
+
+ wordLen = popPS()
+ wordAddr = popPS()
+ word = getString(wordAddr, wordLen)
+
+ createHeader(word, 0)
+
+ return mem[NEXT]
+end)
+
+COMMA = defPrim(",", () -> begin
+ mem[mem[HERE]] = popPS()
+ mem[HERE] += 1
+
+ return mem[NEXT]
+end)
+
+LBRAC = defPrim("[", () -> begin
+ mem[STATE] = 0
+ return mem[NEXT]
+end, flags=F_IMMED)
+
+RBRAC = defPrim("]", () -> begin
+ mem[STATE] = 1
+ return mem[NEXT]
+end, flags=F_IMMED)
+
+HIDDEN = defPrim("HIDDEN", () -> begin
+ addr = popPS() + 1
+ mem[addr] = mem[addr] $ F_HIDDEN
+ return mem[NEXT]
+end)
+
+HIDE = defWord("HIDE",
+ [WORD,
+ FIND,
+ HIDDEN,
+ EXIT])
+
+COLON = defWord(":",
+ [WORD,
+ CREATE,
+ LIT, DOCOL, COMMA,
+ LATEST, FETCH, HIDDEN,
+ RBRAC,
+ EXIT])
+
+SEMICOLON = defWord(";",
+ [LIT, EXIT, COMMA,
+ LATEST, FETCH, HIDDEN,
+ LBRAC,
+ EXIT], flags=F_IMMED)
+
+IMMEDIATE = defPrim("IMMEDIATE", () -> begin
+ lenAndFlagsAddr = mem[LATEST] + 1
+ mem[lenAndFlagsAddr] = mem[lenAndFlagsAddr] $ F_IMMED
+ return mem[NEXT]
+end, flags=F_IMMED)
+
+TICK = defWord("'", [WORD, FIND, TOCFA, EXIT])
+
+# Branching
+
+BRANCH = defPrim("BRANCH", () -> begin
+ reg.IP += mem[reg.IP]
+ return mem[NEXT]
+end)
+
+ZBRANCH = defPrim("0BRANCH", () -> begin
+ if (popPS() == 0)
+ reg.IP += mem[reg.IP]
+ else
+ reg.IP += 1
+ end
+
+ return mem[NEXT]
+end)
+
+# Strings
+
+LITSTRING = defPrim("LITSTRING", () -> begin
+ len = mem[reg.IP]
+ reg.IP += 1
+ pushPS(reg.IP)
+ pushPS(len)
+ reg.IP += len
+
+ return mem[NEXT]
+end)
+
+TELL = defPrim("TELL", () -> begin
+ len = popPS()
+ addr = popPS()
+ str = getString(addr, len)
+ print(str)
+ return mem[NEXT]
+end)
+
+# Outer interpreter
+
+INTERPRET = defPrim("INTERPRET", () -> begin
+
+ callPrim(mem[WORD])
+
+ wordName = getString(mem[reg.PSP-1], mem[reg.PSP])
+ println("... ", replace(wordName, "\n", "\\n"), " ...")
+
+ callPrim(mem[TWODUP])
+ callPrim(mem[FIND])
+
+ wordAddr = mem[reg.PSP]
+
+
+ if wordAddr>0
+ # Word in dictionary
+
+ isImmediate = (mem[wordAddr+1] & F_IMMED) != 0
+ callPrim(mem[TOCFA])
+
+ callPrim(mem[ROT]) # get rid of extra copy of word string details
+ popPS()
+ popPS()
+
+ if mem[STATE] == 0 || isImmediate
+ # Execute!
+ return mem[popPS()]
+ else
+ # Append CFA to dictionary
+ callPrim(mem[COMMA])
+ end
+ else
+ # Not in dictionary, assume number
+
+ popPS()
+
+ callPrim(mem[NUMBER])
+
+ if popPS() != 0
+ println("Parse error at word: '$wordName'")
+ return mem[NEXT]
+ else
+ end
+
+ if mem[STATE] == 0
+ # Number already on stack!
+ else
+ # Append literal to dictionary
+ pushPS(LIT)
+ callPrim(mem[COMMA])
+ callPrim(mem[COMMA])
+ end
+ end
+
+ return mem[NEXT]
+end)
+
+QUIT = defWord("QUIT",
+ [RSP0_CFA, RSPSTORE,
+ INTERPRET,
+ BRANCH,-2])
+
+NL = defPrim("\n", () -> begin
+ if mem[STATE] == 0
+ println(" ok")
+ end
+ return mem[NEXT]
+end)
+
+# Odds and Ends
+
+CHAR = defPrim("CHAR", () -> begin
+ callPrim(mem[WORD])
+ wordLen = popPS()
+ wordAddr = popPS()
+ word = getString(wordAddr, wordLen)
+ pushPS(Int64(word[1]))
+
+ return mem[NEXT]
+end)
+
+EXECUTE = defPrim("EXECUTE", () -> begin
+ return mem[popPS()]
+end)
+
+BYE = defPrim("BYE", () -> begin
+ return 0
+end)
+
+#### VM loop ####
+function runVM()
+ # Start with IP pointing to first instruction of outer interpreter
+ reg.IP = QUIT + 1
+
+ # Primitive processing loop.
+ # Everyting else is simply a consequence of this loop!
+ jmp = mem[NEXT]
+ while (jmp = callPrim(jmp)) != 0
+ println("Evaluating prim $jmp [$(primNames[-jmp])]")