Added CODE/END-CODE.

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

diff --git a/src/forth.jl b/src/forth.jl
index 3d5fbd5..51714f4 100644 (file)
--- a/src/forth.jl
+++ b/src/forth.jl
@@ -48,13 +48,26 @@ function ensurePSDepth(depth::Int64)
     end
 end
 
+function ensurePSCapacity(toAdd::Int64)
+    if reg.PSP + toAdd >= PSP0 + size_PS
+        error("Parameter stack overflow.")
+    end
+end
+
 function ensureRSDepth(depth::Int64)
     if reg.RSP - RSP0 < depth
         error("Return stack underflow.")
     end
 end
 
+function ensureRSCapacity(toAdd::Int64)
+    if reg.RSP + toAdd >= RSP0 + size_RS
+        error("Return stack overflow.")
+    end
+end
+
 function pushRS(val::Int64)
+    ensureRSCapacity(1)
     mem[reg.RSP+=1] = val
 end
 
@@ -67,6 +80,8 @@ function popRS()
 end
 
 function pushPS(val::Int64)
+    ensurePSCapacity(1)
+
     mem[reg.PSP += 1] = val
 end
 
@@ -1015,6 +1030,43 @@ IMMEDIATE_CFA = defPrimWord("IMMEDIATE", () -> begin
     return NEXT
 end, flags=F_IMMED)
 
+CODE_CFA = defPrimWord("CODE", () -> begin
+    pushPS(32)
+    callPrim(mem[WORD_CFA])
+    callPrim(mem[HEADER_CFA])
+
+    exprString = "() -> begin\n"
+    while true
+        if mem[TOIN] >= mem[NUMTIB]
+            println()
+            exprString = string(exprString, "\n")
+
+            pushPS(TIB)
+            pushPS(160)
+            callPrim(mem[EXPECT_CFA])
+            mem[NUMTIB] = mem[SPAN]
+            mem[TOIN] = 0
+        end
+
+        pushPS(32)
+        callPrim(mem[WORD_CFA])
+        cAddr = popPS()
+        thisWord = getString(cAddr+1, mem[cAddr])
+
+        if uppercase(thisWord) == "END-CODE"
+            break
+        end
+
+        exprString = string(exprString, " ", thisWord)
+    end
+    exprString = string(exprString, "\nreturn NEXT\nend")
+
+    func = eval(parse(exprString))
+    dictWrite(defPrim(func))
+
+    return NEXT
+end)
+
 # Outer Interpreter
 
 EXECUTE_CFA = defPrimWord("EXECUTE", () -> begin