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--- at:tutorial:objects [2007/06/27 12:02] – jorge
+++ at:tutorial:objects [2007/06/27 14:09] – jorge
@@ Line 21: / Line 21: @@
 </code>
-Objects are defined using the *def* keyword. The state of the ''Point'' object is composed of ''x'' and ''y'' fields and its behaviour corresponds to the ''init'' and ''sumOfSquares'' methods.
+As all definitions in AmbientTalk, objects are defined using the **def** keyword. In the example above, the state of the ''Point'' object is composed of ''x'' and ''y'' fields and its behaviour corresponds to the ''init'' and ''sumOfSquares'' methods.
 This object can be instantiated to create new points as follows:
 <code>
-> def initialPoint := Point.new(0,0)
+> def aPoint := Point.new(2,3)
 >><object:13393187>
 </code>
-Every object understands the message new, which creates a clone (a shallow copy) of the receiver object and initializes the clone by invoking its init method with the arguments that were passed to new. Hence, the init method plays the role of “constructor” for AmbientTalk objects. AmbientTalk’s object instantiation protocol closely corresponds to class instantiation in class-based languages, except that the new object is a clone of an existing object, rather than an empty object allocated from a class.
+Every object understands the message ''new'', which creates a clone (a shallow copy) of the receiver object and initializes the clone by invoking its ''init'' method with the arguments that were passed to new (''xCoord'' and ''yCoord'' in the example of the ''Point'' object). Hence, the ''init'' method plays the role of “constructor” for AmbientTalk objects. AmbientTalk’s object instantiation protocol closely corresponds to class instantiation in class-based languages, except that the new object is a clone of an existing object, rather than an empty object allocated from a class. We further explain the semantics of object cloning in subsection [[objects#Delegation_and_cloning|Delegation and cloning]].
 ===== Sending messages =====
-In AmbientTalk, computation is expressed in terms of object sending messages to one another.
+In AmbientTalk, computation is expressed in terms of objects sending messages to one another.
+Object's fields and methods are accessed as follows:
+<code>
+> aPoint.x
+>>2
+> aPoint.sumOfSquares()
+>>13
+</code>
+<note important>
+AmbientTalk supports both traditional canonical syntax (e.g. ''o.m(a,b,c)'') as well as keyworded syntax (e.g. ''o.at: key put: value'') for method definitions and message sends.
+</note>
 ===== Cloning and instantiation =====