# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1480436851 -3600
# Node ID d16731ea85682b0ee1dd95e675bf630dfaafb9be
# Parent  661a64c3c23729f5ca867ace14b253a1c1069f1e
Introduced default results for certain operators instead of raising TypeError.
Removed a reminder comment that should be placed elsewhere.

diff -r 661a64c3c237 -r d16731ea8568 lib/operator/comparison.py
--- a/lib/operator/comparison.py	Tue Nov 29 17:25:54 2016 +0100
+++ b/lib/operator/comparison.py	Tue Nov 29 17:27:31 2016 +0100
@@ -3,7 +3,7 @@
 """
 Operator support.
 
-Copyright (C) 2010, 2013, 2015 Paul Boddie <paul@boddie.org.uk>
+Copyright (C) 2010, 2013, 2015, 2016 Paul Boddie <paul@boddie.org.uk>
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -25,13 +25,10 @@
 # lambda functions. Thus, the appropriate methods are defined locally, but no
 # attempt to obtain them is made until the generic function is called.
 
-# NOTE: The compiler should make it possible for the following functions to call
-# NOTE: the generic operator implementations with no additional call overhead.
-
 # Comparison functions.
 
 def eq(a, b):
-    return binary_op(a, b, lambda a: a.__eq__, lambda b: b.__eq__)
+    return binary_op(a, b, lambda a: a.__eq__, lambda b: b.__eq__, False)
 
 def ge(a, b):
     return binary_op(a, b, lambda a: a.__ge__, lambda b: b.__le__)
@@ -46,6 +43,6 @@
     return binary_op(a, b, lambda a: a.__lt__, lambda b: b.__gt__)
 
 def ne(a, b):
-    return binary_op(a, b, lambda a: a.__ne__, lambda b: b.__ne__)
+    return binary_op(a, b, lambda a: a.__ne__, lambda b: b.__ne__, True)
 
 # vim: tabstop=4 expandtab shiftwidth=4
diff -r 661a64c3c237 -r d16731ea8568 lib/operator/core.py
--- a/lib/operator/core.py	Tue Nov 29 17:25:54 2016 +0100
+++ b/lib/operator/core.py	Tue Nov 29 17:27:31 2016 +0100
@@ -24,7 +24,7 @@
 
 from native import _is as is_, _is_not as is_not
 
-def binary_op(a, b, left_accessor, right_accessor):
+def binary_op(a, b, left_accessor, right_accessor, default=None):
 
     """
     A single parameterised function providing the binary operator mechanism for
@@ -57,11 +57,14 @@
             return result
 
     # Where no methods were available, or if neither method could support the
-    # operation, raise an exception.
+    # operation, raise an exception or provide a default result.
 
-    raise TypeError
+    if default is None:
+        raise TypeError
+    else:
+        return default
 
-def unary_op(a, accessor):
+def unary_op(a, accessor, default=None):
 
     """
     A single parameterised function providing the unary operator mechanism for
@@ -81,9 +84,12 @@
             return result
 
     # Where no method was available, or if the method could not support the
-    # operation, raise an exception.
+    # operation, raise an exception or provide a default result.
 
-    raise TypeError
+    if default is None:
+        raise TypeError
+    else:
+        return default
 
 def augassign(a, b, augmented_accessor, left_accessor, right_accessor):