Editing BPMN (section)

=====XOR or Data-based Exclusive Gateway=====
*also called 'split and merge'
*exactly one outgoing path gets the token
*graphical X can be ommitted
*issues:
** only one outgoing path gets the token, but what if condition leads to two, who will be the first and only (evaluation number)
** better to define a default path if condition leads to no path
*if the condition leads to no or more than one outgoing paths is a modelling error, if the process is executed such that none of the conditional Expressions evaluates to true, a runtime exception occurs
*merge if one incoming branch (it does not block additional tokens that come after the first one)