The 'data' property

Any APL array or overlay

Valid for: All objects

The data property allows you to associate arbitrary APL data with any object. The APL data can be retrieved later, for example during a callback function. The data is stored outside the workspace, in system memory.

Using the data property can help make your applications better structured, allowing information associated with an object to be stored with it rather than held in global variables in the workspace.

If you reference the data property before assigning to it, APLX reports a VALUE ERROR.

You can also assign arbitrary APL data to 'delta' properties, allowing you to have as many distinct variables associated with an object as you like.

Special considerations for Client-Server versions of APLX

Because the whole System Class sub-system runs on the Client machine, the data contained in the data property is held (in memory) on the Client machine, as a variable in APLX 32-bit format (even if the APL session which wrote the variable is a 64-bit implementation of APLX). The data must therefore be representable as a 32-bit object, which means it must be smaller than 2GB and must not contain more than 2147483647 elements. An array which contains 64-bit integer numbers of magnitude bigger than 2*31 will be converted to float data, and precision may be lost.