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

diff --git a/lib/standard/kernel.nit b/lib/standard/kernel.nit
index 26498fe..01e72e3 100644
--- a/lib/standard/kernel.nit
+++ b/lib/standard/kernel.nit
@@ -226,6 +226,25 @@ interface Discrete
 	end
 end
 
+# Something that can be cloned
+#
+# This interface introduces the `clone` method used to duplicate an instance
+# Its specific semantic is let to the subclasses.
+interface Cloneable
+	# Duplicate `self`
+	#
+	# The specific semantic of this method is let to the subclasses;
+	# Especially, if (and how) attributes are cloned (depth vs. shallow).
+	#
+	# As a rule of thumb, the principle of least astonishment should
+	# be used to guide the semantic.
+	#
+	# Note that as the returned clone depends on the semantic,
+	# the `==` method, if redefined, should ensure the equality
+	# between an object and its clone.
+	fun clone: SELF is abstract
+end
+
 # A numeric value supporting mathematical operations
 interface Numeric
 	super Comparable
@@ -285,7 +304,8 @@ end
 # `true` and `false` are the only instances.
 #
 # Boolean are manipulated trough three special operators:
-#	 `and`, `or`, `not`.
+# `and`, `or`, `not`.
+#
 # Booleans are mainly used by conditional statement and loops.
 universal Bool
 	redef fun object_id is intern
@@ -698,6 +718,22 @@ universal Char
 	do
 		return is_lower or is_upper
 	end
+
+	# Is self a whitespace character?
+	#
+	# These correspond to the "Other" and "Separator" groups of the Unicode.
+	#
+	# In the ASCII encoding, this is those <= to space (0x20) plus delete (0x7F).
+	#
+	#     assert 'A'.is_whitespace  == false
+	#     assert ','.is_whitespace  == false
+	#     assert ' '.is_whitespace  == true
+	#     assert '\t'.is_whitespace == true
+	fun is_whitespace: Bool
+	do
+		var i = ascii
+		return i <= 0x20 or i == 0x7F
+	end
 end
 
 # Pointer classes are used to manipulate extern C structures.
@@ -706,5 +742,5 @@ extern class Pointer
 	fun address_is_null: Bool is extern "address_is_null"
 
 	# Free the memory pointed by this pointer
-	fun free `{ free(recv); `}
+	fun free is extern "free"
 end