(Adding message template to the top of the page) |
(Replacing message template with parser tag) |
||
Line 1: | Line 1: | ||
<message>Write the content here to display this box</message> | |||
In MDriven, we want to change data when appropriate – so we use the same syntax as OCL in something we call EAL – ExtendedActionLanguage. | In MDriven, we want to change data when appropriate – so we use the same syntax as OCL in something we call EAL – ExtendedActionLanguage. | ||
Revision as of 07:41, 17 June 2024
In MDriven, we want to change data when appropriate – so we use the same syntax as OCL in something we call EAL – ExtendedActionLanguage.
We use EAL in MDriven here:
- Action execute expression
- Actions in ViewModel columns Execute expression
- Class method implementations
- StateMachine Effects
EAL Differences
When using EAL, one often wants to stack expressions after each other. To allow for this, EAL has introduced an expression separator: The semicolon ;
. This means that you can build method bodies that do several things like this:
self.SomeDateTime := DateTime.Now; self.SomeInt := 27; self.SomeString := self.SomeDateTime.ToString('yyyy-MM-dd')
In EAL, we use :=
to assign but =
to compare.
In EAL, we can also create new objects Thing.Create
Worth noting is that the expression separator ;
can only be used between statements. So writing this ‘a string’;0
is of type integer. But writing this ‘a string’;0;
is of unknown type and hence wrong – the last statement that the parser expects after the last ;
is not found.