X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;ds=sidebyside;f=src%2Fforth.jl;h=37ce5d1a7e01f478dda01b87f3efcc3290a7fda4;hb=a02d0aced80ab33dad899f91106ede749882b883;hp=63e7d576e70e3af8d8855ccb5f9cb932bb0fb81a;hpb=19d08aee45587ac2b84f6c413fc53542d50c52cc;p=forth.jl.git

diff --git a/src/forth.jl b/src/forth.jl
index 63e7d57..37ce5d1 100644
--- a/src/forth.jl
+++ b/src/forth.jl
@@ -17,15 +17,15 @@ primNames = Array{ASCIIString,1}()
 
 nextVarAddr = 1
 H = nextVarAddr; nextVarAddr += 1              # Next free memory address
-FORTH_LATEST = nextVarAddr; nextVarAddr += 1   # LFA of latest word in system dict
+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[FORTH_LATEST] = 0               # no previous definition
-mem[CURRENT] = FORTH_LATEST         # Compile words to system dict initially
+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
 
@@ -117,8 +117,8 @@ 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[mem[H]] = mem[mem[CURRENT]+1]
+    mem[mem[CURRENT]+1] = mem[H]
     mem[H] += 1
 
     dictWrite(length(name) | flags | NFA_MARK)
@@ -213,7 +213,6 @@ end)
 # Dictionary entries for core built-in variables, constants
 
 H_CFA = defExistingVar("H", H)
-CURRENT_CFA = defExistingVar("CURRENT", CURRENT)
 
 PSP0_CFA = defConst("PSP0", PSP0)
 RSP0_CFA = defConst("RSP0", RSP0)
@@ -708,51 +707,49 @@ FROMLINK_CFA = defPrimWord("LINK>", () -> begin
     return NEXT
 end)
 
+NUMCONTEXT, NUMCONTEXT_CFA = defNewVar("#CONTEXT", 1)
+
 createHeader("FORTH", 0)
 FORTH_CFA = mem[H]
 dictWrite(defPrim(() -> begin
-    mem[CONTEXT] = reg.W
+    mem[CONTEXT + mem[NUMCONTEXT] - 1] = reg.W
     return NEXT
 end, name="FORTH"))
-dictWrite(FORTH_LATEST)
+dictWrite(0) # cell for latest
 
-CONTEXT, CONTEXT_CFA = defNewVar("CONTEXT", zeros(Int64, 100))
-mem[CONTEXT] = FORTH_CFA
-NUMCONTEXT, NUMCONTEXT_CFA = defNewVar("#CONTEXT", 1)
+CURRENT_CFA = defExistingVar("CURRENT", CURRENT)
 
-FIND_CFA = defPrimWord("FIND", () -> begin
+# 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))
 
-    context = mem[CONTEXT:(CONTEXT+mem[NUMCONTEXT]-1)]
-
+    lfa = vocabCFA+1
     lenAndFlags = 0
-    lfa = 0
-
-    for vocabCFA in reverse(context)
-        lfa = mem[vocabCFA+1]
 
-        while (lfa = mem[lfa]) > 0
+    while (lfa = mem[lfa]) > 0
 
-            lenAndFlags = mem[lfa+1]
-            len = lenAndFlags & F_LENMASK
-            hidden = (lenAndFlags & F_HIDDEN) == F_HIDDEN
+        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
+        if hidden || len != wordLen
+            continue
         end
 
-        if lfa>0
+        thisWord = lowercase(getString(lfa+2, len))
+
+        if thisWord == word
             break
         end
     end
@@ -773,6 +770,31 @@ FIND_CFA = defPrimWord("FIND", () -> begin
     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
 
@@ -893,7 +915,7 @@ end, name="DODOES")
 
 DOES_HELPER_CFA = defPrimWord("(DOES>)", () -> begin
 
-    pushPS(mem[mem[CURRENT]])
+    pushPS(mem[mem[CURRENT]+1])
     callPrim(mem[FROMLINK_CFA])
     cfa = popPS()
 
@@ -923,7 +945,7 @@ RBRAC_CFA = defPrimWord("]", () -> begin
 end, flags=F_IMMED)
 
 HIDDEN_CFA = defPrimWord("HIDDEN", () -> begin
-    lenAndFlagsAddr = mem[mem[CURRENT]] + 1
+    lenAndFlagsAddr = mem[mem[CURRENT]+1] + 1
     mem[lenAndFlagsAddr] = mem[lenAndFlagsAddr] $ F_HIDDEN
     return NEXT
 end)
@@ -943,7 +965,7 @@ SEMICOLON_CFA = defWord(";",
     EXIT_CFA], flags=F_IMMED)
 
 IMMEDIATE_CFA = defPrimWord("IMMEDIATE", () -> begin
-    lenAndFlagsAddr = mem[mem[CURRENT]] + 1
+    lenAndFlagsAddr = mem[mem[CURRENT]+1] + 1
     mem[lenAndFlagsAddr] = mem[lenAndFlagsAddr] $ F_IMMED
     return NEXT
 end, flags=F_IMMED)