simulation v7.0.0

New features

• Support for ModelJSON import and export
• New function, Model.check() that checks for some classes of errors (such as syntax errors) across a model without running a simulation

Other changes

• Unicode letters and number characters can now be used in identifiers and units
• Improved error reporting
• Using [Alpha] and [Omega] as aliases for the start and end of flows and transitions is no longer supported
• The onPause configuration parameter to simulateAsync has been replaced with onStep which is called on every time step
• Other miscellaneous improvements