train vs fit

[simonpcouch]

The method to fit a tailor is called fit() and a new helper function calls that operation fitting:

tailor/R/utils.R

Lines 76 to 81 in e98131d

	#' @export
	#' @keywords internal
	#' @rdname tailor-internals
	tailor_requires_fit <- function(x) {
	any(purrr::map_lgl(x$operations, tailor_operation_requires_fit))
	}

At the same time, some other functionality (printing, the slot $trained, the following helper) uses train:

tailor/R/utils.R

Lines 64 to 70 in e98131d

	tailor_fully_trained <- function(x) {
	if (length(x$operations) == 0L) {
	return(FALSE)
	}
	all(purrr::map_lgl(x$operations, tailor_operation_trained))
	}

train follows the precedent of recipes::fully_trained(), print methods elsewhere, etc. I'm not sure if this might be a point of confusion for users.

[topepo]

I'm wondering if we should differentiate between "trained", "untrained", and "n/a". The last case is things like probability thresholding that don't estimate anything.

[simonpcouch]

The requires_fit slot can help us tell which operations don't estimate anything!