+ return NEXT
+end)
+
+HERE_CFA = defWord("HERE",
+ [H_CFA, FETCH_CFA, EXIT_CFA])
+
+HEADER_CFA = defPrimWord("HEADER", () -> begin
+ wordAddr = popPS()+1
+ wordLen = mem[wordAddr-1]
+ word = getString(wordAddr, wordLen)
+
+ createHeader(word, 0)
+
+ return NEXT
+end)
+
+CREATE_CFA = defWord("CREATE",
+ [LIT_CFA, 32, WORD_CFA, HEADER_CFA,
+ LIT_CFA, DOVAR, COMMA_CFA,
+ EXIT_CFA])
+
+DODOES = defPrim(() -> begin
+ pushRS(reg.IP)
+ reg.IP = popPS()
+ pushPS(reg.W + 1)
+ return NEXT
+end, name="DODOES")
+
+DOES_HELPER_CFA = defPrimWord("(DOES>)", () -> begin
+
+ pushPS(mem[mem[CURRENT]+1])
+ callPrim(mem[FROMLINK_CFA])
+ cfa = popPS()
+
+ runtimeAddr = popPS()
+
+ mem[cfa] = defPrim(eval(:(() -> begin
+ pushPS($(runtimeAddr))
+ return DODOES
+ end)), name="doesPrim")
+
+ return NEXT
+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,
+ LIT_CFA, DOES_HELPER_CFA, COMMA_CFA, LIT_CFA, EXIT_CFA, COMMA_CFA, EXIT_CFA],
+ flags=F_IMMED)
+
+LBRAC_CFA = defPrimWord("[", () -> begin
+ mem[STATE] = 0
+ return NEXT
+end, flags=F_IMMED)
+
+RBRAC_CFA = defPrimWord("]", () -> begin
+ mem[STATE] = 1
+ return NEXT
+end, flags=F_IMMED)
+
+HIDDEN_CFA = defPrimWord("HIDDEN", () -> begin
+ lenAndFlagsAddr = mem[mem[CURRENT]+1] + 1
+ mem[lenAndFlagsAddr] = xor(mem[lenAndFlagsAddr], F_HIDDEN)
+ return NEXT
+end)
+
+COLON_CFA = defWord(":",
+ [LIT_CFA, 32, WORD_CFA,
+ HEADER_CFA,
+ LIT_CFA, DOCOL, COMMA_CFA,
+ HIDDEN_CFA,
+ RBRAC_CFA,
+ EXIT_CFA])
+
+SEMICOLON_CFA = defWord(";",
+ [LIT_CFA, EXIT_CFA, COMMA_CFA,
+ HIDDEN_CFA,
+ LBRAC_CFA,
+ EXIT_CFA], flags=F_IMMED)
+
+IMMEDIATE_CFA = defPrimWord("IMMEDIATE", () -> begin
+ lenAndFlagsAddr = mem[mem[CURRENT]+1] + 1
+ mem[lenAndFlagsAddr] = xor(mem[lenAndFlagsAddr], F_IMMED)
+ return NEXT
+end, flags=F_IMMED)
+
+# ( addr n -- primAddr )
+CREATE_PRIM_CFA = defPrimWord("CREATE-PRIM", () -> begin
+ len = popPS()
+ addr = popPS()
+
+ exprString = string("() -> begin\n",
+ getString(addr, len), "\n",
+ "return NEXT\n",
+ "end")
+ func = eval(parse(exprString))
+
+ pushPS(defPrim(func))
+ return NEXT
+end)
+
+# Outer Interpreter
+
+EXECUTE_CFA = defPrimWord("EXECUTE", () -> begin
+ reg.W = popPS()
+ return mem[reg.W]
+end)
+
+INTERPRET_CFA = defWord("INTERPRET",
+ [LIT_CFA, 32, WORD_CFA, # Read next space-delimited word
+
+ DUP_CFA, FETCH_CFA, ZE_CFA, ZBRANCH_CFA, 3,
+ DROP_CFA, EXIT_CFA, # Exit if input buffer is exhausted
+
+ STATE_CFA, FETCH_CFA, ZBRANCH_CFA, 24,
+ # Compiling
+ FIND_CFA, QDUP_CFA, ZBRANCH_CFA, 13,
+
+ # Found word.
+ LIT_CFA, -1, EQ_CFA, INVERT_CFA, ZBRANCH_CFA, 4,
+
+ # Immediate: Execute!
+ EXECUTE_CFA, BRANCH_CFA, -26,
+
+ # Not immediate: Compile!
+ COMMA_CFA, BRANCH_CFA, -29,
+
+ # No word found, parse number
+ NUMBER_CFA, LIT_CFA, LIT_CFA, COMMA_CFA, COMMA_CFA, BRANCH_CFA, -36,
+
+ # Interpreting
+ FIND_CFA, QDUP_CFA, ZBRANCH_CFA, 5,
+
+ # Found word. Execute!
+ DROP_CFA, EXECUTE_CFA, BRANCH_CFA, -44,
+
+ # No word found, parse number and leave on stack
+ NUMBER_CFA, BRANCH_CFA, -47,
+ EXIT_CFA])
+
+PROMPT_CFA = defPrimWord("PROMPT", () -> begin
+ if mem[STATE] == 0
+ print(" ok")
+ end
+ println()
+
+ return NEXT
+end)
+
+QUIT_CFA = defWord("QUIT",
+ [LIT_CFA, 0, STATE_CFA, STORE_CFA, # Set mode to interpret
+ LIT_CFA, 0, SOURCE_ID_VAR_CFA, STORE_CFA, # Set terminal as input stream
+ LIT_CFA, 0, NUMTIB_CFA, STORE_CFA, # Clear the input buffer
+ RSP0_CFA, RSPSTORE_CFA, # Clear the return stack
+ QUERY_CFA, # Read line of input
+ INTERPRET_CFA, PROMPT_CFA, # Interpret line
+ BRANCH_CFA,-4]) # Loop
+
+INCLUDED_CFA = defWord("INCLUDED",
+ [LIT_CFA, 0, STATE_CFA, STORE_CFA, # Set mode to interpret
+ FAM_RO_CFA, OPEN_FILE_CFA, DROP_CFA, # Open the file
+ SOURCE_ID_VAR_CFA, FETCH_CFA, SWAP_CFA, # Store current source on stack
+ SOURCE_ID_VAR_CFA, STORE_CFA, # Mark this as the current source
+ SOURCE_ID_VAR_CFA, FETCH_CFA, QUERY_FILE_CFA, # Read line from file
+ EOF_FLAG_CFA, FETCH_CFA,
+ NUMFIB_CFA, FETCH_CFA, ZE_CFA, AND_CFA, # Test for EOF and empty line
+ INVERT_CFA, ZBRANCH_CFA, 4, # Break out if EOF
+ INTERPRET_CFA, # Interpret line
+ BRANCH_CFA, -14, # Loop
+ SOURCE_ID_VAR_CFA, FETCH_CFA,
+ CLOSE_FILE_CFA, DROP_CFA, # Close file
+ SOURCE_ID_VAR_CFA, STORE_CFA, # Restore input source
+ LIT_CFA, 0, NUMIB_CFA, STORE_CFA, # Zero #IB
+ LIT_CFA, 0, TOIN_CFA, STORE_CFA, # Zero >IN
+ EXIT_CFA])
+
+INCLUDE_CFA = defWord("INCLUDE", [LIT_CFA, 32, WORD_CFA,
+ DUP_CFA, INCR_CFA,
+ SWAP_CFA, FETCH_CFA,
+ INCLUDED_CFA, EXIT_CFA]);
+
+ABORT_CFA = defWord("ABORT",
+ [CLOSE_FILES_CFA, DROP_CFA, PSP0_CFA, PSPSTORE_CFA, QUIT_CFA])
+
+BYE_CFA = defPrimWord("BYE", () -> begin
+ if mem[SOURCE_ID_VAR] == 0
+ println("\nBye!")
+ end
+ return 0
+end)
+
+EOF_CFA = defPrimWord("\x04", () -> begin
+ return 0
+end)
+
+### Library loading ###
+
+oldCWD = ""
+SETLIBCWD_CFA = defPrimWord("SETLIBCWD", () -> begin
+ global oldCWD = pwd()
+ if !isfile("lib.4th") # Exception for debugging.
+ cd(Pkg.dir("forth","src"))
+ end
+ return NEXT
+end)
+
+RESTORECWD_CFA = defPrimWord("RESTORECWD", () -> begin
+ cd(oldCWD)
+ return NEXT
+end)
+
+INCLUDED_LIB_CFA = defWord("INCLUDED-LIB",
+ [SETLIBCWD_CFA, INCLUDED_CFA, RESTORECWD_CFA, EXIT_CFA])
+
+INCLUDE_LIB_CFA = defWord("INCLUDE-LIB", [LIT_CFA, 32, WORD_CFA,
+ DUP_CFA, INCR_CFA,
+ SWAP_CFA, FETCH_CFA,
+ INCLUDED_LIB_CFA, EXIT_CFA]);
+
+SKIP_WELCOME, SKIP_WELCOME_CFA = defNewVar("SKIP-WELCOME", 0)
+
+#### VM loop ####
+
+initialized = false
+libFileName = "lib.4th"
+
+function run(fileName=nothing; initialize=true)
+
+ # Start with IP pointing to first instruction of outer interpreter
+ pushRS(QUIT_CFA+1)
+
+ # Include optional file
+ if fileName != nothing
+ putString(fileName, mem[H])
+ pushPS(mem[H])
+ mem[H] += length(fileName)
+ pushPS(length(fileName))
+ pushRS(INCLUDED_CFA+1)
+
+ mem[SKIP_WELCOME] = -1
+ end
+
+ # Load library files
+ global initialized, libFileName
+ if !initialized && initialize
+ if libFileName != nothing
+ #print("Including definitions from $libFileName...")
+
+ putString(libFileName, mem[H])
+ pushPS(mem[H])
+ pushPS(length(libFileName))
+ pushRS(INCLUDED_LIB_CFA+1)
+
+ initialized = true