Retrieve formulas from model objects

This function is primarily an internal helper function in `jtools`

and
related packages to standardize the different types of formula objects used
by different types of models.

get_formula(model, ...)
# S3 method for default
get_formula(model, ...)
# S3 method for brmsfit
get_formula(model, resp = NULL, dpar = NULL, ...)

## Arguments

model |
The fitted model object. |

... |
Ignored. |

resp |
For `brmsfit` objects, the response variable for which
the formula is desired. `brmsfit` objects may have multiple formulas, so
this selects a particular one. If `NULL` , the first formula is chosen
(unless `dpar` is specified). |

dpar |
For `brmsfit` objects, the distributional variable for which
the formula is desired. If `NULL` , no distributional parameter is used.
If there are multiple responses with distributional parameters, then
`resp` should be specified or else the first formula will be used by
default. |

## Examples

#> mpg ~ cyl
#> <environment: 0x0000000036083ed8>