# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1479831656 -3600
# Node ID fe05975a4b54e3062c1e9a4a79574e6522e0c183
# Parent  1a64c775111a787b29d9a8cffaa54a43c690975d
Added support for unary negation of integers.

diff -r 1a64c775111a -r fe05975a4b54 lib/__builtins__/int.py
--- a/lib/__builtins__/int.py	Tue Nov 22 01:28:58 2016 +0100
+++ b/lib/__builtins__/int.py	Tue Nov 22 17:20:56 2016 +0100
@@ -131,8 +131,14 @@
         return _negate(self.__eq__(other))
 
     def __invert__(self): pass
-    def __neg__(self): pass
-    def __pos__(self): pass
+
+    def __neg__(self):
+        "Apply the unary negation operator."
+        return native._int_neg(self)
+
+    def __pos__(self):
+        "Apply the unary positive operator."
+        return self
 
     def __str__(self):
         "Return a string representation."
diff -r 1a64c775111a -r fe05975a4b54 lib/native.py
--- a/lib/native.py	Tue Nov 22 01:28:58 2016 +0100
+++ b/lib/native.py	Tue Nov 22 17:20:56 2016 +0100
@@ -30,6 +30,7 @@
 def _int_div(self, other): pass
 def _int_mod(self, other): pass
 def _int_mul(self, other): pass
+def _int_neg(self): pass
 def _int_pow(self, other): pass
 def _int_sub(self, other): pass
 
diff -r 1a64c775111a -r fe05975a4b54 templates/native.c
--- a/templates/native.c	Tue Nov 22 01:28:58 2016 +0100
+++ b/templates/native.c	Tue Nov 22 17:20:56 2016 +0100
@@ -153,6 +153,17 @@
     #undef other
 }
 
+__attr __fn_native__int_neg(__attr __args[])
+{
+    #define self (__args[1])
+    /* self.__data__ interpreted as int */
+    int i = __load_via_object(self.value, __pos___data__).intvalue;
+
+    /* Return the new integer. */
+    return __new_int(-i);
+    #undef self
+}
+
 __attr __fn_native__int_pow(__attr __args[])
 {
     #define self (__args[1])
diff -r 1a64c775111a -r fe05975a4b54 templates/native.h
--- a/templates/native.h	Tue Nov 22 01:28:58 2016 +0100
+++ b/templates/native.h	Tue Nov 22 17:20:56 2016 +0100
@@ -14,6 +14,7 @@
 __attr __fn_native__int_div(__attr __args[]);
 __attr __fn_native__int_mod(__attr __args[]);
 __attr __fn_native__int_mul(__attr __args[]);
+__attr __fn_native__int_neg(__attr __args[]);
 __attr __fn_native__int_pow(__attr __args[]);
 __attr __fn_native__int_sub(__attr __args[]);
 
diff -r 1a64c775111a -r fe05975a4b54 tests/list.py
--- a/tests/list.py	Tue Nov 22 01:28:58 2016 +0100
+++ b/tests/list.py	Tue Nov 22 17:20:56 2016 +0100
@@ -5,3 +5,7 @@
 print l[1]
 print l[2]
 print l[3]
+print l[-1]
+print l[-2]
+print l[-3]
+print l[-4]