Documentation:OCLOperators value: Difference between revisions

OCLOperators value

Revision as of 13:38, 19 June 2024

Returns the the non-null value of a simple nullable type.

Expression	Result
int? with the value null	0

The value of the current nullable object is returned if it has been assigned a valid underlying value otherwise 0 is returned.

Some expressions may require a non null value and yet your attribute is a nullable type. A scenario like this is catered for in MDriven OCL expressions.

For example

To calculate the Total Price of all products

Product.allinstances.Price->sum.Valueor

Product.allinstances->collect(i|i.Price.Value)->sum

This will ensure a value is always returned by the expression either when there are no product instances or product price is not set for all instances

This page was edited 7 days ago on 06/24/2024. What links here

@@ Line 8: / Line 8: @@
 |0
 |}
-{{Edited|July|12|2024}}
+{{Edited|July|12|2024}}The value of the current nullable object is returned if it has been assigned a valid underlying value otherwise 0 is returned.
+Some expressions may require  a non null value and yet your attribute is a nullable type. A scenario like this is catered for in MDriven OCL expressions.
+For example
+[[File:getting-value-for-nullable-type.png|alt=getting value for nullable type|frameless]]
+To calculate the Total Price of all products
+<code>Product.allinstances.Price->sum.Value</code>or
+<code>Product.allinstances->collect(i|i.Price.Value)->sum</code>
+This will ensure a value is always returned by the expression either when there are no product instances or product price is not set for all instances