From b18e42773e45b9d4819cf0e2d2c5965bd34dcb4f Mon Sep 17 00:00:00 2001
From: Tim Vaughan <tgvaughan@gmail.com>
Date: Fri, 27 May 2016 00:03:40 +1200
Subject: [PATCH] Reimplemented EXPECT.  Closes #1.

---
 README.md               | 12 +++----
 examples/mandelbrot.4th |  4 ++-
 src/forth.jl            | 78 +++++++++++++++++++++++++++++++++++------
 src/lib.4th             |  3 ++
 4 files changed, 77 insertions(+), 20 deletions(-)

diff --git a/README.md b/README.md
index 612de1a..f43eb80 100644
--- a/README.md
+++ b/README.md
@@ -37,14 +37,8 @@ the julia prompt:
 The first thing the interpreter will do is compile the core definitions in
 the library file.  Once this is complete you can start entering forth commands:
 
-    : star 42 emit ;
-     ok
-    star
-    * ok
-
-Notice that unlike other forths, forth.jl echos a newline after reading each
-line of standard input.  This is an unfortunate side-effect of the way that
-I've implemented EXPECT.  Hopefully I'll be able to fix this in future.
+    : star 42 emit ;  ok
+    star * ok
 
 There's an example Mandelbrot Set drawing program included in the examples
 directory.  To run it, you'll have to locate this directory on your system (its
@@ -86,6 +80,8 @@ my system I can run the example in this way:
                                                                            **                       
     ok
 
+To exit, enter ^D on a blank line or use the `bye` word.
+
 ## License
 
 This package is free software and is distributed under version 3.0 of the GNU
diff --git a/examples/mandelbrot.4th b/examples/mandelbrot.4th
index b8af203..9759a39 100644
--- a/examples/mandelbrot.4th
+++ b/examples/mandelbrot.4th
@@ -76,6 +76,8 @@
 ( Draw the Mandelbrot Set!)
 : mandeldraw ( x1 y1 x2 y2 -- )
 
+    cr
+
     0 pick 3 pick - ysteps /
     1 pick 4 pick do
 
@@ -106,4 +108,4 @@ hide *
         mandeldraw
 ;
 
-.( Enter 'mandel' to draw the Mandelbrot Set.)
+CR .( Enter 'mandel' to draw the Mandelbrot Set.)
diff --git a/src/forth.jl b/src/forth.jl
index 04771ea..4b71499 100644
--- a/src/forth.jl
+++ b/src/forth.jl
@@ -607,8 +607,8 @@ sources = Array{Any,1}()
 currentSource() = sources[length(sources)]
 
 EOF = defPrimWord("\x04", () -> begin
-    close(pop!(sources))
-    if !isempty(sources)
+    if currentSource() != STDIN
+        close(pop!(sources))
         return NEXT
     else
         return 0
@@ -626,27 +626,82 @@ function raw_mode!(mode::Bool)
     end
 end
 
-KEY = defPrimWord("KEY", () -> begin
+function getKey()
     raw_mode!(true)
-    pushPS(Int(readbytes(STDIN, 1)[1]))
+    byte = readbytes(STDIN, 1)[1]
     raw_mode!(false)
+
+    if byte == 0x0d
+        return 0x0a
+    elseif byte == 127
+        return 0x08
+    else
+        return byte
+    end
+end
+
+KEY = defPrimWord("KEY", () -> begin
+    pushPS(Int(getKey()))
     return NEXT
 end)
 
+function getLineFromSTDIN()
+    line = ""
+    while true
+        key = Char(getKey())
+
+        if key == '\n'
+            print(" ")
+            return ASCIIString(line)
+
+        elseif key == '\x04'
+            if isempty(line)
+                return string("\x04")
+            end
+
+        elseif key == '\b'
+            if !isempty(line)
+                line = line[1:length(line)-1]
+                print("\b \b")
+            end
+
+        elseif key == '\e'
+            # Strip ANSI escape sequence
+            nextKey = Char(getKey())
+            if nextKey == '['
+                while true
+                    nextKey = Char(getKey())
+                    if nextKey >= '@' || nextKey <= '~'
+                        break
+                    end
+                end
+            end
+
+        else
+            print(key)
+            line = string(line, key)
+        end
+    end
+end
+
 SPAN, SPAN_CFA = defNewVar("SPAN", 0)
 EXPECT = defPrimWord("EXPECT", () -> begin
     maxLen = popPS()
     addr = popPS()
 
-    if !eof(currentSource())
-        line = chomp(readline(currentSource()))
-        mem[SPAN] = min(length(line), maxLen)
-        putString(line[1:mem[SPAN]], addr)
+    if currentSource() == STDIN
+        line = getLineFromSTDIN()
     else
-        mem[SPAN] = 1
-        mem[addr] = 4 # eof
+        if !eof(currentSource())
+            line = chomp(readline(currentSource()))
+        else
+            line = "\x04" # eof
+        end
     end
 
+    mem[SPAN] = min(length(line), maxLen)
+    putString(line[1:mem[SPAN]], addr)
+
     return NEXT
 end)
 
@@ -855,7 +910,7 @@ PARSE = defPrimWord("PARSE", () -> begin
 end)
 
 BYE = defPrimWord("BYE", () -> begin
-    println("Bye!")
+    println("\nBye!")
     return 0
 end)
 
@@ -1131,6 +1186,7 @@ DUMP = defPrimWord("DUMP", () -> begin
     count = popPS()
     addr = popPS()
 
+    println()
     dump(addr, count=count)
 
     return NEXT
diff --git a/src/lib.4th b/src/lib.4th
index 664ff80..8da2fb1 100644
--- a/src/lib.4th
+++ b/src/lib.4th
@@ -587,6 +587,7 @@ DOES>   @
 ;
 
 : WORDS
+        CR
         LATEST @        ( start at LATEST dictionary entry )
         BEGIN
                 ?DUP            ( while link pointer is not null )
@@ -619,6 +620,8 @@ DOES>   @
 : SEE
         BL WORD FIND    ( find the dictionary entry to decompile )
 
+        CR
+
         0= IF
                 ." Word '" COUNT TYPE ." ' not found in dictionary."
                 EXIT
-- 
2.20.1