X-Git-Url: http://nitlanguage.org

diff --git a/lib/standard/kernel.nit b/lib/standard/kernel.nit
index 259eac1..fb84d2e 100644
--- a/lib/standard/kernel.nit
+++ b/lib/standard/kernel.nit
@@ -17,6 +17,10 @@ module kernel
 
 import end # Mark this module is a top level one. (must be only one)
 
+`{
+#include <errno.h>
+`}
+
 ###############################################################################
 # System Classes                                                              #
 ###############################################################################
@@ -84,6 +88,11 @@ end
 class Sys
 	# Instructions outside classes implicitly redefine this method.
 	fun main do end
+
+	# Number of the last error
+	fun errno: Int is extern `{
+		return errno;
+	`}
 end
 
 ###############################################################################
@@ -230,6 +239,14 @@ interface Numeric
 
 	# The value of zero in the domain of `self`
 	fun zero: OTHER is abstract
+
+	# The value of `val` in the domain of `self`
+	#
+	#     assert 1.0.value_of(2) == 2.0
+	#     assert 1.0.value_of(2.0) == 2.0
+	#     assert 1.value_of(2) == 2
+	#     assert 1.value_of(2.0) == 2
+	fun value_of(val: Numeric): OTHER is abstract
 end
 
 ###############################################################################
@@ -284,6 +301,7 @@ universal Float
 	redef fun to_f do return self
 
 	redef fun zero do return 0.0
+	redef fun value_of(val) do return val.to_f
 end
 
 # Native integer numbers.
@@ -316,6 +334,7 @@ universal Int
 	fun %(i: Int): Int is intern
 
 	redef fun zero do return 0
+	redef fun value_of(val) do return val.to_i
 
 	# `i` bits shift fo the left (aka <<)
 	#
@@ -591,9 +610,9 @@ universal Char
 end
 
 # Pointer classes are used to manipulate extern C structures.
-extern Pointer
+extern class Pointer
 	# Is the address behind this Object at NULL?
-	fun address_is_null: Bool `{ return recv == NULL; `}
+	fun address_is_null: Bool is extern "address_is_null"
 
 	# Free the memory pointed by this pointer
 	fun free `{ free(recv); `}