if(!app.dirExists()) throw new NodeDoesNotExistException(app, this);
if(!bladeset.dirExists()) throw new NodeDoesNotExistException(bladeset, this);
if(blade.dirExists()) throw new NodeAlreadyExistsException(blade, this);
try {
blade.populate();
}
catch(InvalidNameException e) {
throw new CommandArgumentsException(e, this);
}
catch(ModelUpdateException e) {