View source for Documentation:OCLOperators union

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=== union ( bag : Bag(T) ) : Bag(T) ===
Returns a Bag containing all elements of ''self'' and all elements of *bag*. 
{| class="wikitable"
!Expression
!Result
|-
|Bag{'a', 'b', 'a'}->union(Bag{'b', 'c'})
|Bag{'a', 'b', 'a', 'c'}
|-
|Set{1,2,3}->union(Set{2,3,4})
|Set{1,2,3,4}
|}
[[File:2019-11-25 13h28 15.png|none|thumb]]

Video: https://www.youtube.com/watch?v=-vBshXtEPts

{{Edited|July|12|2025}}'''Example 1: Bags'''


Expression:<syntaxhighlight lang="abap">
Bag{'a', 'b', 'a'}->union(Bag{'b', 'c'})

</syntaxhighlight>Result:<syntaxhighlight lang="abap">
Bag{'a', 'b', 'a', 'c'}

</syntaxhighlight>

* All elements from both Bags are included.

* <code>'a'</code> appears twice because Bags allow duplicates.



'''Example 2: Sets'''
Expression:<syntaxhighlight lang="abap">
Set{1,2,3}->union(Set{2,3,4})

</syntaxhighlight>Result:<syntaxhighlight lang="abap">
Set{1,2,3,4}

</syntaxhighlight>

* All unique elements from both Sets are included.

* Duplicates are automatically removed.

[[Category:Intermediate-Friendly]]
[[Category:OCL (Object Constraint Language)]]
[[Category:OCL Operators: Collection Navigation]]
[[Category:Priority 50]]