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at:tutorial:basic [2008/03/12 17:16] tvcutsemat:tutorial:basic [2009/06/05 15:32] – added tvcutsem
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 </code> </code>
  
-In that case, the //sum// function still accepts an arbitrary number of arguments as long as two arguments are supplied. //a// and //b// are considered as mandatory arguments of the argument list. +In that case, the //sum// function still accepts an arbitrary number of arguments as long as two arguments are supplied. //a// and //b// are considered as mandatory arguments of the argument list. 
 + 
 +The splice operator can also be used to transform a table into an argument list for a function, for example: 
 +<code> 
 +def args := [3,4,5]; 
 +> sum(1,2, @args); 
 +>> 15 
 +</code> 
 + 
 +One way to think about this is that the splice operator splices the ''args'' table into the table of actual arguments. The "rest" arguments do not necessarily need to be the last parameters, for example: 
 +<code> 
 +> sum(1,2,@args,6); 
 +>> 21 
 +</code> 
 + 
 +==== Optional Parameters ====
  
 A function can also declare optional arguments as shown below. Optional arguments can be omitted in a function call. If this is the case, the default expression provided in their definition is evaluated and passed as argument to the function instead. A function can also declare optional arguments as shown below. Optional arguments can be omitted in a function call. If this is the case, the default expression provided in their definition is evaluated and passed as argument to the function instead.
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   def i := 0;   def i := 0;
   def mapped[tbl.length] {   def mapped[tbl.length] {
-    clo(tbl[i:=i+1])+    i := i+1
 +    clo( tbl[ i ] )
   };   };
 } }
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 Control flow constructs are defined in the lexical root of AmbientTalk. The lexical root is an object containing globally visible native methods (i.e. it is the top-level environment). We have already seen in the previous sections examples of use of the foreach and if/then structures. A list of traditional control flow structures defined in AmbientTalk is shown below: Control flow constructs are defined in the lexical root of AmbientTalk. The lexical root is an object containing globally visible native methods (i.e. it is the top-level environment). We have already seen in the previous sections examples of use of the foreach and if/then structures. A list of traditional control flow structures defined in AmbientTalk is shown below:
 <code> <code>
-if: booleanCondition then: consequent +if: booleanCondition then: consequentClosure 
-if: booleanCondition then: consequent else: alternative+if: booleanCondition then: consequentClosure else: alternativeClosure
 while: conditionClosure do: body while: conditionClosure do: body
 foreach: iteratorClosure in: table foreach: iteratorClosure in: table
Line 424: Line 440:
  
 <note warn> <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 that ''conditionClosure'' 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> </note>
  
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     table;     table;
   };   };
-  quickSort(table, 1, table.getLength());+  quickSort(table, 1, table.length);
 }; };
 >><closure:sort> >><closure:sort>
at/tutorial/basic.txt · Last modified: 2020/02/09 22:05 by elisag