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    Slice expressions
    
    

    
    

    
    

    
    
    
    

    



    

        Sorted expressions

        Sorted expressions are used to produce a sorted list from an existing collection.

            A Sorted expression is a code fragment which produces a list, whose item type is the same as the item type of the collection being sorted,
            which can then be used as an input for other operations: print, write, method call and so forth.

            A Sorted expression has the form sorted collection
            where collection is a collection value.

        
        The type of the resulting value is the same as the List value.


        
Using native sorting

        Sorting a collection of simple values is done using native sorting, as follows:

        
            
        

        Sorting

        Sorting backwards is done by inserting the descending keyword after the sorted one.

        In O and M dialects, the desc abbreviated keyword is preferred.

        
            
        

        Sorting a collection of custom objects

        When sorting custom objects there is no natural order. It is therefore necessary to specify how to compare custom objects.

        This is done by using a key on which exists a natural order.

        Sorting lists of custom objects by existing key attribute

        When a custom object comprises a key, this attribute is used to sort a collection implicitly.

        
            
        

        Sorting lists of custom objects by any attribute

        Any native attribute can be used to sort a collection explicitly.

        
            
        

        Sorting lists of custom objects by expression

        Alternately, lists of custom objects can be sorted using expressions as key, as follows: