Some integration with Type Checking.

Now the UI highlights commands and numbers as you move the mouse, numbers
are blue, commands that type-check are green, commands that fail to
type-check are orange and will not be interpreted, and if there is no
stack effect information available for a command it is grey but you can
still attempt to execute it.

You can still evaluate whole expressions by selceting them and
right-inter-clicking before you release the left button, or by putting
the cursor on a line and typing ctrl-enter, which will run the whole
line.  These expressions are NOT (yet) type-checked.

joy/gui/main.py

@@ -19,10 +19,10 @@ from joy.utils.stack import stack_to_string
 
 tb = TEXT_BINDINGS.copy()
 tb.update({
-  '<F4>': lambda tv: tv.cut,
   '<F3>': lambda tv: tv.copy_selection_to_stack,
+  '<F4>': lambda tv: tv.cut,
   #  '<F-->': lambda tv: tv.pastecut,
-  '<F6>': lambda tv: tv.copyto,
+  #  '<F6>': lambda tv: tv.copyto,
   })
 defaults = dict(text_bindings=tb, width=80, height=25)
 

joy/gui/mousebindings.py

@@ -65,6 +65,7 @@ class MouseBindingsMixin:
     self.bind("<ButtonRelease-3>", self.B3r)
 
     self.bind("<Any-Leave>", self.leave)
+    self.bind("<Motion>", self.scan_command)
 
   def B1d(self, event):
     '''button one pressed'''
@@ -167,6 +168,9 @@ class MouseBindingsMixin:
 
     return "break"
 
+  def scan_command(self, event):
+    self.update_command_word(event)
+
   def B1r(self, event):
     '''button one released'''
     self.B1_DOWN = False

joy/gui/textwidget.py

@@ -164,10 +164,11 @@ class TextViewerWidget(tk.Text, MouseBindingsMixin, SavingMixin):
 
   #These are the config tags for command text when it's highlighted.
   command_tags = dict(
-    underline = 1,
-    bgstipple = "gray50",
-    borderwidth = "1",
-    foreground = "orange"
+    #underline = 1,
+    #bgstipple = "gray50",
+    borderwidth = 2,
+    relief=tk.RIDGE,
+    foreground = "green"
   )
 
   def __init__(self, world, master=None, **kw):
@@ -196,6 +197,9 @@ class TextViewerWidget(tk.Text, MouseBindingsMixin, SavingMixin):
 
     #Add tag config for command highlighting.
     self.tag_config('command', **self.command_tags)
+    self.tag_config('bzzt', foreground = "orange")
+    self.tag_config('huh', foreground = "grey")
+    self.tag_config('number', foreground = "blue")
 
     #Create us a command instance variable
     self.command = ''
@@ -246,18 +250,28 @@ class TextViewerWidget(tk.Text, MouseBindingsMixin, SavingMixin):
       return
 
     cmd, b, e = cmd
-    if self.world.has(cmd) or is_numerical(cmd):
-      self.command = cmd
-      self.highlight_command(
-        '%d.%d' % (row, b),
-        '%d.%d' % (row, e),
-        )
+    if is_numerical(cmd):
+      extra_tags = 'number',
+    elif self.world.has(cmd):
+      check = self.world.check(cmd)
+      if check: extra_tags = ()
+      elif check is None: extra_tags = 'huh',
+      else: extra_tags = 'bzzt',
+    else:
+      return
+    self.command = cmd
+    self.highlight_command(
+      '%d.%d' % (row, b),
+      '%d.%d' % (row, e),
+      *extra_tags)
 
-  def highlight_command(self, from_, to):
+  def highlight_command(self, from_, to, *extra_tags):
     '''Apply command style from from_ to to.'''
     cmdstart = self.index(from_)
     cmdend = self.index(to)
     self.tag_add('command', cmdstart, cmdend)
+    for tag in extra_tags:
+      self.tag_add(tag, cmdstart, cmdend)
 
   def do_command(self, event):
     '''Do the currently highlighted command.'''
@@ -288,6 +302,9 @@ class TextViewerWidget(tk.Text, MouseBindingsMixin, SavingMixin):
 
   def unhighlight_command(self):
     '''Remove any command highlighting.'''
+    self.tag_remove('number', 1.0, tk.END)
+    self.tag_remove('huh', 1.0, tk.END)
+    self.tag_remove('bzzt', 1.0, tk.END)
     self.tag_remove('command', 1.0, tk.END)
 
   def set_insertion_point(self, event):

joy/gui/world.py

@@ -23,6 +23,7 @@ from inspect import getdoc
 from joy.joy import run
 from joy.parser import Symbol
 from joy.utils.stack import stack_to_string
+from joy.utils.polytypes import type_check
 
 
 def is_numerical(s):
@@ -40,6 +41,9 @@ class World(object):
     self.dictionary = dictionary or {}
     self.text_widget = text_widget
 
+  def check(self, name):
+    return type_check(name, self.stack)
+
   def do_lookup(self, name):
     if name in self.dictionary:
       self.stack = (Symbol(name), ()), self.stack
@@ -75,6 +79,10 @@ class World(object):
       return self.stack[0]
 
   def interpret(self, command):
+    if len(command.split()) == 1 and not is_numerical(command):
+      assert self.has(command), repr(command)
+      if self.check(command) == False:  # not in {True, None}:
+        return
     try:
       self.stack, _, self.dictionary = run(
         command,
@@ -109,8 +117,14 @@ class StackDisplayWorld(World):
     self.relative_STACK_FN = rel_filename
 
   def interpret(self, command):
-    print '\njoy?', command
-    super(StackDisplayWorld, self).interpret(command)
+    if (
+      is_numerical(command)
+      or len(command.split()) > 1
+      or self.has(command)
+      and self.check(command) in {True, None}
+      ):
+      print '\njoy?', command
+      super(StackDisplayWorld, self).interpret(command)
 
   def print_stack(self):
     print '\n%s <-' % stack_to_string(self.stack)

joy/utils/polytypes.py

@@ -9,6 +9,7 @@ and we can introduce a kind of Kleene Star or sequence type that can stand for
 an unbounded sequence of other types.
 
 '''
+import sys
 from inspect import stack as inspect_stack
 from itertools import chain, product
 from logging import getLogger
@@ -343,6 +344,31 @@ def infer(*expression):
     return sorted(set(_infer(list_to_stack(expression))))
 
 
+def type_check(name, stack):
+    '''
+    Trinary predicate.  True if named function type-checks, False if it
+    fails, None if it's indeterminate (because I haven't entered it into
+    the FUNCTIONS dict yet.)
+    '''
+    try:
+        func = FUNCTIONS[name]
+    except KeyError:
+        return # None, indicating unknown
+
+    for fi, fo in infer(func):
+        try:
+          U = unify(fi, stack)
+        except JoyTypeError, e:
+            #print e
+            continue
+        except ValueError, e:
+            #print >> sys.stderr, name, e, stack
+            continue
+        #print U
+        return True
+    return False
+
+
 a0, a1, a2, a3, a4, a5, a6, a7, a8, a9 = A
 b0, b1, b2, b3, b4, b5, b6, b7, b8, b9 = B
 n0, n1, n2, n3, n4, n5, n6, n7, n8, n9 = N