Could I use the following sentence, please:
According to the timeStepDirection value (+1 or -1), change the current program number to or fro along the time axis.
If not, is it at least possible to use such combination in a totally informal sentence?
Or "to and fro" is an absolutely immutable idiom?
Sorry, my example was very bad. Eventually I changed "to or fro" here to "appropriately".
But could such form be used in another context?