Differences

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--- at:tutorial:basic [2007/12/28 12:29] – fixed tvcutsem
+++ at:tutorial:basic [2008/03/12 17:16] – tvcutsem
@@ Line 417: / Line 417: @@
 if: booleanCondition then: consequent
 if: booleanCondition then: consequent else: alternative
-while: condition do: body
+while: conditionClosure do: body
-foreach: iteratorclosure in: table
+foreach: iteratorClosure in: table
-do: body if: condition
+do: bodyClosure if: condition
-do: body unless: condition
+do: bodyClosure unless: condition
 </code>
-Note that ''condition'' in the ''while:do:'' construct denotes a //closure// that should return a boolean value. It needs to be a closure because the code is evaluated repeatedly until the closure returns false. ''body'', ''consequent'', ''alternative'' all denote zero-argument closures.
+<note warn>
+Note that ''condition'' in the ''while:do:'' construct denotes a //closure// that should return a boolean value. It needs to be a closure because the code is evaluated repeatedly until the closure returns false. ''bodyClosure'', ''consequentClosure'', ''alternativeClosure'' all denote zero-argument closures. As a general rule, all code that needs to be delayed or executed repeatedly must be wrapped in a closure.
+</note>
-An example of usage for some of these structures is shown below in the definition of the sort function.
+The above definitions in the lexical root of AmbientTalk are simply convenience functions for the methods defined on booleans and closures. For example, an if-statement can also be encoded as a message send, as in Smalltalk: ''boolean.ifTrue: {...} ifFalse: {...}''.
+An example of usage for some of the above structures is shown below in the definition of the sort function.
 <code>
 >def sort(table, cmp := { |e1,e2| e1 < e2 }) {