There are now a number of commands where the user's input for a particular argument could be interpreted by the command in multiple ways; eg. a transform could be a text file with an affine transformation or a warp image, or a set of directions on the unit hemisphere could come from a text file or an image header. To support these cases, we're added the ".type_various()" classification, such that any special handling within the command-line parsing is effectively bypassed. This will also appear in some cases where the command-line interface is exported to text.

What would be a more targeted solution is to allow each argument to receive multiple classifications. So eg. in the examples above, the argument would be classified as being compatible with either an input file or an input image, but not anything else. Any command-line interpretation cleverness would then be compatible with the user providing either of those cases. And exported command-line interface information would more faithfully communicate what is and is not permitted for that argument.

Not sure how much benefit could actually be gained from such---probably not much---but I wanted to document it in case it may be recognised as the solution to some issue.