Some fields in OBO-Edit allow the use of backtick expressions. Backtick expressions are OSL expressions enclosed in ` (backtick) characters.
When a backtick expression is encountered in an appropriate context, the OSL expression is evaluated, and the backtick expression is replaced with the value of the expression.
For example, the following term filter will find all descendants of the currently selected term:
[Ancestor] [ID] [equals] "`GUI.getSubSelection().getID()`"
The backtick expression `GUI.getSubSelection().getID()` will be evaluated and replaced with the ID of the currently selected term.
Backtick expression are allowed in the "value" field of a filter.