# Built-in variables
nextVarAddr = 1
-H = nextVarAddr; nextVarAddr += 1 # Next free memory address
-LATEST = nextVarAddr; nextVarAddr += 1 # LFA of latest word in systetm dict
+H = nextVarAddr; nextVarAddr += 1 # Next free memory address
+FORTH_LATEST = nextVarAddr; nextVarAddr += 1 # LFA of latest word in system dict
+CURRENT = nextVarAddr; nextVarAddr += 1 # Current compilation dict
RSP0 = nextVarAddr # bottom of RS
PSP0 = RSP0 + size_RS # bottom of PS
TIB = PSP0 + size_PS # address of terminal input buffer
mem[H] = TIB + size_TIB # location of bottom of dictionary
-mem[LATEST] = 0 # no previous definition
+mem[FORTH_LATEST] = 0 # no previous definition
+mem[CURRENT] = FORTH_LATEST # Compile words to system dict initially
DICT = mem[H] # Save bottom of dictionary as constant
F_HIDDEN = 64
NFA_MARK = 128
+function dictWrite(ints::Array{Int64,1})
+ mem[mem[H]:(mem[H]+length(ints)-1)] = ints
+ mem[H] += length(ints)
+end
+dictWrite(int::Int64) = dictWrite([int])
+dictWriteString(string::ASCIIString) = dictWrite([Int64(c) for c in string])
+
function createHeader(name::AbstractString, flags::Int64)
- mem[mem[H]] = mem[LATEST]
- mem[LATEST] = mem[H]
+ mem[mem[H]] = mem[mem[CURRENT]]
+ mem[mem[CURRENT]] = mem[H]
mem[H] += 1
- mem[mem[H]] = length(name) | flags | NFA_MARK; mem[H] += 1
- putString(name, mem[H]); mem[H] += length(name)
+ dictWrite(length(name) | flags | NFA_MARK)
+ dictWriteString(name)
end
function defPrimWord(name::AbstractString, f::Function; flags::Int64=0)
createHeader(name, flags)
codeWordAddr = mem[H]
- mem[codeWordAddr] = defPrim(f, name=name)
- mem[H] += 1
+ dictWrite(defPrim(f, name=name))
return codeWordAddr
end
createHeader(name, flags)
addr = mem[H]
- mem[mem[H]] = DOCOL
- mem[H] += 1
+ dictWrite(DOCOL)
- for wordAddr in wordAddrs
- mem[mem[H]] = wordAddr
- mem[H] += 1
- end
+ dictWrite(wordAddrs)
return addr
end
codeWordAddr = mem[H]
varAddr = mem[H] + 1
- mem[mem[H]] = DOVAR; mem[H] += 1
- mem[mem[H]:(mem[H]+length(initial)-1)] = initial; mem[H] += length(initial)
+ dictWrite(DOVAR)
+ dictWrite(initial)
return varAddr, codeWordAddr
end
codeWordAddr = mem[H]
- mem[mem[H]] = DOCON; mem[H] += 1
- mem[mem[H]] = val; mem[H] += 1
+ dictWrite(DOCON)
+ dictWrite(val)
return codeWordAddr
end
# Dictionary entries for core built-in variables, constants
H_CFA = defExistingVar("H", H)
-LATEST_CFA = defExistingVar("LATEST", LATEST)
+CURRENT_CFA = defExistingVar("CURRENT", CURRENT)
PSP0_CFA = defConst("PSP0", PSP0)
RSP0_CFA = defConst("RSP0", RSP0)
# Dictionary searches
-TOCFA_CFA = defPrimWord(">CFA", () -> begin
+FROMLINK_CFA = defPrimWord("LINK>", () -> begin
addr = popPS()
lenAndFlags = mem[addr+1]
return NEXT
end)
-TOBODY_CFA = defWord(">BODY", [INCR_CFA, EXIT_CFA])
+createHeader("FORTH", 0)
+FORTH_CFA = mem[H]
+dictWrite(defPrim(() -> begin
+ mem[CONTEXT] = reg.W
+ return NEXT
+end, name="FORTH"))
+dictWrite(FORTH_LATEST)
+
+CONTEXT, CONTEXT_CFA = defNewVar("CONTEXT", zeros(Int64, 100))
+mem[CONTEXT] = FORTH_CFA
+NUMCONTEXT, NUMCONTEXT_CFA = defNewVar("#CONTEXT", 1)
FIND_CFA = defPrimWord("FIND", () -> begin
wordLen = mem[countedAddr]
word = lowercase(getString(wordAddr, wordLen))
- latest = LATEST
+ context = mem[CONTEXT:(CONTEXT+mem[NUMCONTEXT]-1)]
+
lenAndFlags = 0
-
- 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
+ lfa = 0
+
+ for vocabCFA in reverse(context)
+ lfa = mem[vocabCFA+1]
+
+ while (lfa = mem[lfa]) > 0
+
+ lenAndFlags = mem[lfa+1]
+ len = lenAndFlags & F_LENMASK
+ hidden = (lenAndFlags & F_HIDDEN) == F_HIDDEN
+
+ if hidden || len != wordLen
+ continue
+ end
+
+ thisWord = lowercase(getString(lfa+2, len))
+
+ if thisWord == word
+ break
+ end
end
-
- thisAddr = latest+2
- thisWord = lowercase(getString(thisAddr, len))
- if lowercase(thisWord) == lowercase(word)
+ if lfa>0
break
end
end
- if latest > 0
- pushPS(latest)
- callPrim(mem[TOCFA_CFA])
+ if lfa > 0
+ pushPS(lfa)
+ callPrim(mem[FROMLINK_CFA])
if (lenAndFlags & F_IMMED) == F_IMMED
pushPS(1)
else
DOES_HELPER_CFA = defPrimWord("(DOES>)", () -> begin
- pushPS(mem[LATEST])
- callPrim(mem[TOCFA_CFA])
+ pushPS(mem[mem[CURRENT]])
+ callPrim(mem[FROMLINK_CFA])
cfa = popPS()
runtimeAddr = popPS()
end)), name="doesPrim")
return NEXT
-end, flags=F_IMMED)
+end, flags=F_IMMED | F_HIDDEN)
DOES_CFA = defWord("DOES>",
[LIT_CFA, LIT_CFA, COMMA_CFA, HERE_CFA, LIT_CFA, 3, ADD_CFA, COMMA_CFA,
end, flags=F_IMMED)
HIDDEN_CFA = defPrimWord("HIDDEN", () -> begin
- lenAndFlagsAddr = mem[LATEST] + 1
+ lenAndFlagsAddr = mem[mem[CURRENT]] + 1
mem[lenAndFlagsAddr] = mem[lenAndFlagsAddr] $ F_HIDDEN
return NEXT
end)
EXIT_CFA], flags=F_IMMED)
IMMEDIATE_CFA = defPrimWord("IMMEDIATE", () -> begin
- lenAndFlagsAddr = mem[LATEST] + 1
+ lenAndFlagsAddr = mem[mem[CURRENT]] + 1
mem[lenAndFlagsAddr] = mem[lenAndFlagsAddr] $ F_IMMED
return NEXT
end, flags=F_IMMED)