lazyeval.R

df_mean <- function(df, variable) {
  lazyeval::f_interp(~ mean(uq(variable)), data = df)
}

df_mean(mtcars, ~cyl)

## Error in lazyeval::f_interp(~mean(uq(variable)), data = df): could not find function "uq"

df_mean <- function(df, variable) {
  lazyeval::f_interp(~ mean(lazyeval::uq(variable)), data = df)
}

df_mean(mtcars, ~cyl)

## ~mean(lazyeval::uq(variable))
## <environment: 0x4f25068>

library(lazyeval)

df_mean <- function(df, variable) {
  lazyeval::f_interp(~ mean(uq(variable)), data = df)
}

df_mean(mtcars, ~cyl)

## ~mean(c(6, 6, 4, 6, 8, 6, 8, 4, 4, 6, 6, 8, 8, 8, 8, 8, 8, 4, 
## 4, 4, 4, 8, 8, 8, 8, 4, 4, 4, 8, 6, 8, 4))
## <environment: 0x382f638>