Documentation:OCLOperators nullValue: Difference between revisions

OCLOperators nullValue

Latest revision as of 05:58, 11 February 2025

This page was created by Alexandra on 2017-08-13. Last edited by Stephanie@mdriven.net on 2025-02-11.

A typed null value, used to assign a null value to an attribute, a variable or return null from a method.

someobject.someattribute := <Type>.nullValue

Do not use <Type>.nullValue to compare something to null, like this

vCurrent_UppdragTyp = Uppdragstyp.nullValue    -- WRONG

For comparing to null, use the operators .isNull or .notNull

@@ Line 1: / Line 1: @@
-A typed null value
+<message>Write the content here to display this box</message>
-[[Category:OCLOperators]]
+A typed null value, used to assign a null value to an attribute, a variable or return null from a method.
+ someobject.someattribute := <Type>.nullValue
+Do '''not''' use <Type>.nullValue to compare something to null, like this
+ vCurrent_UppdragTyp = Uppdragstyp.nullValue    -- WRONG
+For comparing to null, use the operators [[Documentation:OCLOperators isNull|.isNull]] or [[Documentation:OCLOperators notNull|.notNull]]
+[[Category:OCL General Operators]]
+{{Edited|July|12|2025}}