# Handy functions for adding/retrieving strings to/from memory.
getString(addr::Int64, len::Int64) = ASCIIString([Char(c) for c in mem[addr:(addr+len-1)]])
+
function putString(str::ASCIIString, addr::Int64)
mem[addr:(addr+length(str)-1)] = [Int64(c) for c in str]
end
function defPrim(f::Function; name="nameless")
push!(primitives, f)
- push!(primNames, replace(replace(name, "\004", "EOF"), "\n", "\\n"))
+ push!(primNames, replace(name, "\004", "EOF"))
return -length(primitives)
end
-callPrim(addr::Int64) = primitives[-addr]()
+function callPrim(addr::Int64)
+ if addr >=0 || -addr>length(primitives)
+ error("Attempted to execute non-existent primitive at address $addr.")
+ else
+ primitives[-addr]()
+ end
+end
getPrimName(addr::Int64) = primNames[-addr]
# Word creation functions
sources = Array{Any,1}()
currentSource() = sources[length(sources)]
-EOF_CFA = defConst("EOF", 4)
+EOF = defPrimWord("\x04", () -> begin
+ close(pop!(sources))
+ if !isempty(sources)
+ return NEXT
+ else
+ return 0
+ end
+end)
EMIT = defPrimWord("EMIT", () -> begin
print(Char(popPS()))
putString(line[1:mem[SPAN]], addr)
else
mem[SPAN] = 1
- mem[addr] = EOF
+ mem[addr] = 4 # eof
end
return NEXT
return NEXT
end)
-TODFA = defWord(">DFA", [TOCFA, INCR, EXIT])
+TOPFA = defWord(">PFA", [TOCFA, INCR, EXIT])
# Branching
# Outer interpreter
TRACE = defPrimWord("TRACE", () -> begin
- print("RS: "); printRS()
+ println("reg.W: $(reg.W) reg.IP: $(reg.IP)")
print("PS: "); printPS()
+ print("RS: "); printRS()
print("[paused]")
readline()
# Start reading in word
count = 0
- while (mem[TOIN]<mem[NUMTIB] && mem[TIB+mem[TOIN]] != delim)
+ while (mem[TOIN]<mem[NUMTIB])
mem[addr] = mem[TIB+mem[TOIN]]
+ mem[TOIN] += 1
+
+ if (mem[addr] == delim)
+ break
+ end
+
count += 1
addr += 1
- mem[TOIN] += 1
end
# Record count
return NEXT
end)
+PARSE = defPrimWord("PARSE", () -> begin
+ delim = popPS()
+
+ # Chew up initial occurrences of delim
+ addr = mem[HERE]
+
+ # Start reading input stream
+ count = 0
+ while (mem[TOIN]<mem[NUMTIB])
+ mem[addr] = mem[TIB+mem[TOIN]]
+ mem[TOIN] += 1
+
+ if (mem[addr] == delim)
+ break
+ end
+
+ count += 1
+ addr += 1
+ end
+
+ pushPS(addr)
+ pushPS(count)
+
+ return NEXT
+end)
+
+BYE = defPrimWord("BYE", () -> begin
+ println("Bye!")
+ return 0
+end)
+
STATE, STATE_CFA = defNewVar("STATE", 0)
INTERPRET = defWord("INTERPRET",
DUP, FETCH, ZE, ZBRANCH, 3,
DROP, EXIT, # Exit if TIB is exhausted
- STATE_CFA, FETCH, ZBRANCH, 27,
+ STATE_CFA, FETCH, ZBRANCH, 31,
# Compiling
- DUP, FIND, ZBRANCH, 17,
+ DUP, FIND, QDUP, ZBRANCH, 19,
# Found word.
+ SWAP, DROP,
DUP, TOCFA, SWAP, INCR, FETCH, LIT, F_IMMED, AND, ZBRANCH, 4,
# Immediate: Execute!
- EXECUTE, BRANCH, -30,
+ EXECUTE, BRANCH, -33,
# Not immediate: Compile!
- COMMA, BRANCH, -33,
+ COMMA, BRANCH, -36,
# No word found, parse number
- NUMBER, BTICK, LIT, COMMA, BRANCH, -39,
+ NUMBER, BTICK, LIT, COMMA, COMMA, BRANCH, -43,
# Interpreting
- DUP, FIND, ZBRANCH, 5,
+ DUP, FIND, QDUP, ZBRANCH, 7,
# Found word. Execute!
- TOCFA, EXECUTE, BRANCH, -47,
+ SWAP, DROP, TOCFA, EXECUTE, BRANCH, -54,
# No word found, parse number and leave on stack
- NUMBER, BRANCH, -50,
+ NUMBER, BRANCH, -57,
EXIT]
)
INTERPRET, PROMPT,
BRANCH,-4])
-BYE = defPrimWord("BYE", () -> begin
- return 0
-end)
-
INCLUDE = defPrimWord("INCLUDE", () -> begin
+ pushPS(32)
callPrim(mem[WORD])
- wordLen = popPS()
- wordAddr = popPS()
+ wordAddr = popPS()+1
+ wordLen = mem[wordAddr-1]
word = getString(wordAddr, wordLen)
push!(sources, open(word, "r"))
# Compilation
HEADER = defPrimWord("HEADER", () -> begin
-
wordAddr = popPS()+1
wordLen = mem[wordAddr-1]
word = getString(wordAddr, wordLen)
end)
HIDE = defWord("HIDE",
- [WORD,
+ [LIT, 32, WORD,
FIND,
HIDDEN,
EXIT])
COLON = defWord(":",
- [WORD,
+ [LIT, 32, WORD,
HEADER,
LIT, DOCOL, COMMA,
LATEST_CFA, FETCH, HIDDEN,
return NEXT
end, flags=F_IMMED)
-TICK = defWord("'",
- [WORD, FIND, TOCFA, EXIT])
-
#### VM loop ####
initFileName = Pkg.dir("forth/src/lib.4th")
end
-function run(;initialize=false)
+function run(;initialize=true)
# Begin with STDIN as source
push!(sources, STDIN)
# Everyting else is simply a consequence of this loop!
jmp = NEXT
while jmp != 0
-# try
- println("Entering prim $(getPrimName(jmp))")
+ try
+# println("Entering prim $(getPrimName(jmp))")
jmp = callPrim(jmp)
-# catch ex
-# showerror(STDOUT, ex)
-# println()
-#
-# while !isempty(sources) && currentSource() != STDIN
-# close(pop!(sources))
-# end
-#
-# mem[STATE] = 0
-# mem[NUMTIB] = 0
-# reg.PSP = mem[PSP0]
-# reg.RSP = mem[RSP0]
-# reg.IP = QUIT + 1
-# jmp = NEXT
-# end
+ catch ex
+ showerror(STDOUT, ex)
+ println()
+
+ while !isempty(sources) && currentSource() != STDIN
+ close(pop!(sources))
+ end
+
+ # Want backtrace in here eventually
+ println("reg.W: $(reg.W) reg.IP: $(reg.IP)")
+ print("PS: "); printPS()
+ print("RS: "); printRS()
+
+ mem[STATE] = 0
+ mem[NUMTIB] = 0
+ reg.PSP = mem[PSP0]
+ reg.RSP = mem[RSP0]
+ reg.IP = QUIT + 1
+ jmp = NEXT
+ end
end
end