A language object.
Examples
# Constant variable
a <- 1
# Random uniform variable
b <- rand_uniform()
# Define a closed form expression
cf <- closed_form(omit~omit~3 * (exp(a) + b))
# Only the right hand side of the last `~` will be kept
cf$expr
#> 3 * (exp(a) + b)
d <- rand_normal()
# Define a closed form expression with another closed form expression
cf2 <- closed_form(~cf + 3 * d)
cf2$expr
#> cf + 3 * d