R: Get or set formula components

f_rhs {rlang} | R Documentation

## Get or set formula components

### Description

`f_rhs` extracts the righthand side, `f_lhs` extracts the lefthand side, and `f_env` extracts the environment. All functions throw an error if `f` is not a formula.

### Usage

    f_rhs(f)

    f_rhs(x) <- value

    f_lhs(f)

    f_lhs(x) <- value

    f_env(f)

    f_env(x) <- value

### Arguments

`f, x` | A formula
`value` | The value to replace with.

### Value

`f_rhs` and `f_lhs` return language objects (i.e. atomic vectors of length 1, a name, or a call). `f_env` returns an environment.

### Examples

    f_rhs(~ 1 + 2 + 3)
    f_rhs(~ x)
    f_rhs(~ "A")
    f_rhs(1 ~ 2)

    f_lhs(~ y)
    f_lhs(x ~ y)

    f_env(~ x)

[Package rlang version 0.4.5 Index]