Correct FORTH behaviour implemented.

[forth.jl.git] / src / forth.jl

diff --git a/src/forth.jl b/src/forth.jl
index 57fda1b..63e7d57 100644 (file)
--- a/src/forth.jl
+++ b/src/forth.jl
@@ -16,16 +16,16 @@ primNames = Array{ASCIIString,1}()
 # Built-in variables
 
 nextVarAddr = 1
-H = nextVarAddr; nextVarAddr += 1       # Next free memory address
-FORTH = nextVarAddr; nextVarAddr += 1   # LFA of latest word in system dict
-CURRENT = nextVarAddr; nextVarAddr += 1 # Current compilation 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[FORTH] = 0                      # no previous definition
-mem[CURRENT] = FORTH                # Compile words to system dict initially
+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
 
@@ -109,21 +109,27 @@ F_IMMED = 32
 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[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
@@ -132,13 +138,9 @@ function defWord(name::AbstractString, wordAddrs::Array{Int64,1}; flags::Int64=0
     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
@@ -159,8 +161,8 @@ function defNewVar(name::AbstractString, initial::Array{Int64,1}; flags::Int64=0
     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
@@ -173,8 +175,8 @@ function defConst(name::AbstractString, val::Int64; flags::Int64=0)
 
     codeWordAddr = mem[H]
 
-    mem[mem[H]] = DOCON; mem[H] += 1
-    mem[mem[H]] = val; mem[H] += 1
+    dictWrite(DOCON)
+    dictWrite(val)
 
     return codeWordAddr
 end
@@ -211,7 +213,7 @@ 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)
@@ -695,7 +697,7 @@ end)
 
 # Dictionary searches
 
-LFATOCFA_CFA = defPrimWord("LFA>CFA", () -> begin
+FROMLINK_CFA = defPrimWord("LINK>", () -> begin
 
     addr = popPS()
     lenAndFlags = mem[addr+1]
@@ -706,9 +708,14 @@ LFATOCFA_CFA = defPrimWord("LFA>CFA", () -> begin
     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)
 
-FORTH_CFA = defExistingVar("FORTH", FORTH)
 CONTEXT, CONTEXT_CFA = defNewVar("CONTEXT", zeros(Int64, 100))
 mem[CONTEXT] = FORTH_CFA
 NUMCONTEXT, NUMCONTEXT_CFA = defNewVar("#CONTEXT", 1)
@@ -720,16 +727,16 @@ FIND_CFA = defPrimWord("FIND", () -> begin
     wordLen = mem[countedAddr]
     word = lowercase(getString(wordAddr, wordLen))
 
-    context = mem[CONTEXT:(CONTEXT+mem[NUMCONTEXT])]
+    context = mem[CONTEXT:(CONTEXT+mem[NUMCONTEXT]-1)]
 
     lenAndFlags = 0
     lfa = 0
 
     for vocabCFA in reverse(context)
-        callPrim(mem[vocabCFA])
-        lfa = popPS()
+        lfa = mem[vocabCFA+1]
+
+        while (lfa = mem[lfa]) > 0
 
-        while lfa > 0
             lenAndFlags = mem[lfa+1]
             len = lenAndFlags & F_LENMASK
             hidden = (lenAndFlags & F_HIDDEN) == F_HIDDEN
@@ -738,14 +745,11 @@ FIND_CFA = defPrimWord("FIND", () -> begin
                 continue
             end
 
-            thisAddr = latest+2
-            thisWord = lowercase(getString(thisAddr, len))
+            thisWord = lowercase(getString(lfa+2, len))
 
-            if lowercase(thisWord) == lowercase(word)
+            if thisWord == word
                 break
             end
-
-            lfa = mem[lfa]
         end
 
         if lfa>0
@@ -755,7 +759,7 @@ FIND_CFA = defPrimWord("FIND", () -> begin
 
     if lfa > 0
         pushPS(lfa)
-        callPrim(mem[LFATOCFA_CFA])
+        callPrim(mem[FROMLINK_CFA])
         if (lenAndFlags & F_IMMED) == F_IMMED
             pushPS(1)
         else
@@ -890,7 +894,7 @@ end, name="DODOES")
 DOES_HELPER_CFA = defPrimWord("(DOES>)", () -> begin
 
     pushPS(mem[mem[CURRENT]])
-    callPrim(mem[LFATOCFA_CFA])
+    callPrim(mem[FROMLINK_CFA])
     cfa = popPS()
 
     runtimeAddr = popPS()
@@ -901,7 +905,7 @@ DOES_HELPER_CFA = defPrimWord("(DOES>)", () -> begin
     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,