Remove S3 from model functions #2
Description
Previously, the idea was to figure out the mode from data, so there were different methods for formulas, recipes etc.
However, the mode is manually specified now so we don't need a class for the models (and different methods).
If we kept them, we would need to always specify the mode even when there is on'y one choice (e.g. logistic regression). For example:
> library(parsnip)
> logistic_reg()
Logistic Regression Model Specification (classification)
> logistic_reg(mixture = varying())
Error in varying() : This is a placeholder and should not be evaluated
>
> #we would need to do:
> logistic_reg(mode = "classification", mixture = varying())
Logistic Regression Model Specification (classification)
Main Arguments:
mixture: varying()