docplex.cp.modeler.constant(x) function is not a valid expression

[PhR-IBM]

When using the documented modeler.constant(x) function where x is a constant value, docplex/cp creates a .cpo file for the engine that contains constant(x) as expression. This is not a valid expression for a .cpo file. An error is thus raised when solving the model.

[PhR-IBM]

A possible workaround is to simply use x instead of constant(x).