primitives = Array{Function,1}()
primNames = Array{ASCIIString,1}()
-# Built-in variables
+# Memory geography and built-in variables
nextVarAddr = 1
-H = nextVarAddr; nextVarAddr += 1
-LATEST = nextVarAddr; nextVarAddr += 1
+H = nextVarAddr; nextVarAddr += 1 # Next free memory address
+FORTH_LATEST = nextVarAddr; nextVarAddr += 1 # FORTH dict latest
+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[H] = TIB + size_TIB # location of bottom of dictionary
+mem[FORTH_LATEST] = 0 # zero FORTH dict latest (no previous def)
+mem[CURRENT] = FORTH_LATEST-1 # Compile words to system dict initially
DICT = mem[H] # Save bottom of dictionary as constant
mem[addr:(addr+length(str)-1)] = [Int64(c) for c in str]
end
+stringAsInts(str::ASCIIString) = [Int(c) for c in collect(str)]
+
# Primitive creation and calling functions
function defPrim(f::Function; name="nameless")
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]+1]
+ mem[mem[CURRENT]+1] = 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
end)))
end
-function defNewVar(name::AbstractString, initial::Int64; flags::Int64=0)
+function defNewVar(name::AbstractString, initial::Array{Int64,1}; flags::Int64=0)
createHeader(name, flags)
codeWordAddr = mem[H]
varAddr = mem[H] + 1
- mem[mem[H]] = DOVAR; mem[H] += 1
- mem[mem[H]] = initial; mem[H] += 1
+ dictWrite(DOVAR)
+ dictWrite(initial)
return varAddr, codeWordAddr
end
+defNewVar(name::AbstractString, initial::Int64; flags::Int64=0) =
+ defNewVar(name, [initial]; flags=flags)
+
function defConst(name::AbstractString, val::Int64; flags::Int64=0)
createHeader(name, flags)
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)
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])
+NUMCONTEXT, NUMCONTEXT_CFA = defNewVar("#CONTEXT", 1)
-FIND_CFA = defPrimWord("FIND", () -> begin
+createHeader("FORTH", 0)
+FORTH_CFA = mem[H]
+dictWrite(defPrim(() -> begin
+ mem[CONTEXT + mem[NUMCONTEXT] - 1] = reg.W
+ return NEXT
+end, name="FORTH"))
+dictWrite(0) # cell for latest
+
+CURRENT_CFA = defExistingVar("CURRENT", CURRENT)
+# Switch to new FORTH vocabulary cfa
+mem[FORTH_CFA+1] = mem[mem[CURRENT]+1]
+mem[CURRENT] = FORTH_CFA
+
+CONTEXT, CONTEXT_CFA = defNewVar("CONTEXT", zeros(Int64, 10))
+mem[CONTEXT] = FORTH_CFA
+
+FINDVOCAB_CFA = defPrimWord("FINDVOCAB", () -> begin
+ vocabCFA = popPS()
countedAddr = popPS()
+
wordAddr = countedAddr + 1
wordLen = mem[countedAddr]
word = lowercase(getString(wordAddr, wordLen))
- latest = LATEST
+ lfa = vocabCFA+1
lenAndFlags = 0
-
- i = 0
- while (latest = mem[latest]) > 0
- lenAndFlags = mem[latest+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
-
- thisAddr = latest+2
- thisWord = lowercase(getString(thisAddr, len))
- if lowercase(thisWord) == lowercase(word)
+ thisWord = lowercase(getString(lfa+2, len))
+
+ if thisWord == word
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
return NEXT
end)
+FIND_CFA = defPrimWord("FIND", () -> begin
+
+ countedAddr = popPS()
+ context = mem[CONTEXT:(CONTEXT+mem[NUMCONTEXT]-1)]
+
+ for vocabCFA in reverse(context)
+ pushPS(countedAddr)
+ pushPS(vocabCFA)
+ callPrim(mem[FINDVOCAB_CFA])
+
+ callPrim(mem[DUP_CFA])
+ if popPS() != 0
+ return NEXT
+ else
+ popPS()
+ popPS()
+ end
+ end
+
+ pushPS(countedAddr)
+ pushPS(0)
+
+ return NEXT
+end)
+
# Branching
return NEXT
end)
-BTICK_CFA = defWord("[']",
- [FROMR_CFA, DUP_CFA, INCR_CFA, TOR_CFA, FETCH_CFA, EXIT_CFA])
-
HERE_CFA = defWord("HERE",
[H_CFA, FETCH_CFA, EXIT_CFA])
DOES_HELPER_CFA = defPrimWord("(DOES>)", () -> begin
- pushPS(mem[LATEST])
- callPrim(mem[TOCFA_CFA])
+ pushPS(mem[mem[CURRENT]+1])
+ 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>",
- [BTICK_CFA, LIT_CFA, COMMA_CFA, HERE_CFA, LIT_CFA, 3, ADD_CFA, COMMA_CFA,
- BTICK_CFA, DOES_HELPER_CFA, COMMA_CFA, BTICK_CFA, EXIT_CFA, COMMA_CFA, EXIT_CFA],
+ [LIT_CFA, LIT_CFA, COMMA_CFA, HERE_CFA, LIT_CFA, 3, ADD_CFA, COMMA_CFA,
+ LIT_CFA, DOES_HELPER_CFA, COMMA_CFA, LIT_CFA, EXIT_CFA, COMMA_CFA, EXIT_CFA],
flags=F_IMMED)
LBRAC_CFA = defPrimWord("[", () -> begin
end, flags=F_IMMED)
HIDDEN_CFA = defPrimWord("HIDDEN", () -> begin
- lenAndFlagsAddr = mem[LATEST] + 1
+ lenAndFlagsAddr = mem[mem[CURRENT]+1] + 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] + 1
mem[lenAndFlagsAddr] = mem[lenAndFlagsAddr] $ F_IMMED
return NEXT
end, flags=F_IMMED)
COMMA_CFA, BRANCH_CFA, -29,
# No word found, parse number
- NUMBER_CFA, BTICK_CFA, LIT_CFA, COMMA_CFA, COMMA_CFA, BRANCH_CFA, -36,
+ NUMBER_CFA, LIT_CFA, LIT_CFA, COMMA_CFA, COMMA_CFA, BRANCH_CFA, -36,
# Interpreting
FIND_CFA, QDUP_CFA, ZBRANCH_CFA, 5,
EXIT_CFA])
PROMPT_CFA = defPrimWord("PROMPT", () -> begin
- if (mem[STATE] == 0 && currentSource() == STDIN)
- println(" ok")
+ if currentSource() == STDIN
+ if mem[STATE] == 0
+ print(" ok")
+ end
+ println()
end
return NEXT
wordLen = mem[wordAddr-1]
word = getString(wordAddr, wordLen)
- push!(sources, open(word, "r"))
+ fname = word
+ if !isfile(fname)
+ fname = Pkg.dir("forth","src",word)
+ if !isfile(fname)
+ error("No file named $word found in current directory or package source directory.")
+ end
+ end
+ push!(sources, open(fname, "r"))
# Clear input buffer
mem[NUMTIB] = 0
initFileName = nothing
if isfile("lib.4th")
initFileName = "lib.4th"
-elseif isfile(Pkg.dir("forth/src/lib.4th"))
- initFileName = Pkg.dir("forth/src/lib.4th")
+elseif isfile(Pkg.dir("forth","src", "lib.4th"))
+ initFileName = Pkg.dir("forth","src","lib.4th")
end
function run(;initialize=true)