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List/Set.first


Operator Type: 

Operator Scope of Action: 

Operator Purpose: 

Operator First Added: 

Operator Altered: 

 Property   [other Property type actions]

 List   [operators of similar scope]

 Dictionary, Set & List operations   [other Dictionary, Set & List operations operators]

 9.0.0

 


List/Set.first

Returns the first item of a list. If MyList is a 5-item list "ant;bee;cow;dog;eel":

$MyString = $MyList.first; returns "ant"

List/Set.first(N)

Returns a list of the first N items of a list. With the same list as above:

$MyList2 = $MyList.first(2); returns "ant;bee"

Testing for loop position

This operator can be used to test the current loop state, i.e. whether the currently processed item is the first in the list. Here the code in the commented section is run only when the first list item in $MyList is being processed:

	$MyList.each(anItem){
		if(anItem==$MyList.first){
			// some code here ...
		};
	};

Note that '$MyList.first' is not a test in itself. Rather, it supplies the value of the first list item which can be tested against the currently processed item.

See also List/Set.last.