From: Tim Vaughan <tgvaughan@gmail.com>
Date: Fri, 6 May 2016 08:22:35 +0000 (+1200)
Subject: Implemented COUNT, renamed TELL to TYPE
X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=commitdiff_plain;h=f756abef44feaa53e5f3cf2b7ff2f9bc7940eb10;p=forth.jl.git

Implemented COUNT, renamed TELL to TYPE
---

diff --git a/src/forth.jl b/src/forth.jl
index b1d782c..bf2c8fe 100644
--- a/src/forth.jl
+++ b/src/forth.jl
@@ -857,7 +857,7 @@ LITSTRING = defPrimWord("LITSTRING", () -> begin
     return NEXT
 end)
 
-TELL = defPrimWord("TELL", () -> begin
+TYPE = defPrimWord("TYPE", () -> begin
     len = popPS()
     addr = popPS()
     str = getString(addr, len)
@@ -986,17 +986,7 @@ EOF_WORD = defPrimWord("\x04", () -> begin
     end
 end, flags=F_IMMED)
 
-# Odds and Ends
-
-CHAR = defPrimWord("CHAR", () -> begin
-    callPrim(mem[WORD])
-    wordLen = popPS()
-    wordAddr = popPS()
-    word = getString(wordAddr, wordLen)
-    pushPS(Int64(word[1]))
-
-    return NEXT
-end)
+#### VM loop ####
 
 initialized = false
 initFileName = nothing
@@ -1006,8 +996,6 @@ elseif isfile(Pkg.dir("forth/src/lib.4th"))
     initFileName = Pkg.dir("forth/src/lib.4th")
 end
 
-
-#### VM loop ####
 function run(;initialize=true)
     # Begin with STDIN as source
     push!(sources, STDIN)
diff --git a/src/lib.4th b/src/lib.4th
index 955cadf..c38faa1 100644
--- a/src/lib.4th
+++ b/src/lib.4th
@@ -33,6 +33,11 @@
 
 : LITERAL IMMEDIATE ['] LIT , , ;
 
+: CHAR
+    WORD
+    DROP @
+;
+
 : [CHAR] IMMEDIATE
     CHAR
     ['] LIT , ,
@@ -454,7 +459,7 @@
 
 : ." IMMEDIATE          ( -- )
         [COMPILE] S"    ( read the string, and compile LITSTRING, etc. )
-        ['] TELL ,      ( compile the final TELL )
+        ['] TYPE ,      ( compile the final TYPE )
 ;
 
 : .( 
@@ -469,6 +474,11 @@
         AGAIN
 ;
 
+( Converts address of counted string into address of
+  start of string and length of string. )
+: COUNT ( addr1 -- addr2 n )
+        DUP 1+ SWAP @ ;
+
 
 ( CONSTANTS AND VARIABLES ------------------------------------------------------ )
 
@@ -621,7 +631,14 @@
 ;
 
 : SEE
-        WORD FIND       ( find the dictionary entry to decompile )
+        WORD 2DUP FIND       ( find the dictionary entry to decompile )
+
+        ?DUP 0= IF
+                ." Word '" TYPE ." ' not found in dictionary."
+                EXIT
+        THEN
+
+        -ROT 2DROP
 
         ( Now we search again, looking for the next word in the dictionary.  This gives us
           the length of the word that we will be decompiling.  (Well, mostly it does). )
@@ -684,7 +701,7 @@
                         [CHAR] S EMIT [CHAR] " EMIT SPACE ( print S"<space> )
                         1+ DUP @                ( get the length word )
                         SWAP 1+ SWAP            ( end start+1 length )
-                        2DUP TELL               ( print the string )
+                        2DUP TYPE               ( print the string )
                         [CHAR] " EMIT SPACE          ( finish the string with a final quote )
                         +                       ( end start+1+len, aligned )
                         1-                     ( because we're about to add 4 below )