EXTEND FORM statement
The EXTEND FORM statement extends an existing form.
Syntax
EXTEND FORM formName 
    formBlock1
    ...
    formBlockN
;
Description
The EXTEND FORM statement allows you to extend an existing form with additional form blocks.
Parameters
- 
formNameThe name of the form being extended. Composite ID. 
- 
formBlock1 ... formBlockNForm blocks. 
Example
CLASS ItemGroup;
name = DATA ISTRING[100] (ItemGroup);
itemGroup = DATA ItemGroup (Item);
EXTEND FORM items
    PROPERTIES(i) NEWSESSION DELETE // adding a delete button to the form
    OBJECTS g = ItemGroup BEFORE i // adding a product group object to the form before the product
    PROPERTIES(g) READONLY name
    // if the object was added after the object with products, then filtering would go by the group of products, 
    // and not by products
    FILTERS itemGroup(i) == g 
;