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)
#> 1 + 2 + 3
f_rhs(~ x)
#> x
f_rhs(~ "A")
#> [1] "A"
f_rhs(1 ~ 2)
#> [1] 2
f_lhs(~ y)
#> NULL
f_lhs(x ~ y)
#> x
f_env(~ x)
#> <environment: 0x56292908cac8>
