ryanmonroe

    efficient_flow_agg <- function(dat, col_grouping, gpcol_name="GroupMembership") {
      make_postproc <- function(gp, groups) {
        gp$preproc(dat[gp$which_cols]) |>
          lapply(collapse::BY, groups, gp$aggfun) |>
          gp$postproc()
      }
      col_grouping |>
        lapply(make_postproc, groups = dat[[gpcol_name]]) |>
        as.data.frame()
    }

    df <- tibble(x = list(function(x) x + 1))
    df %>% 
      mutate(y = x[[1]](3))

    log <- 3
    log(1)
    # 0

    frog <- 3
    frog(3)
    # Error in frog(3) : could not find function "frog"
    
    log <- function(x) x^2
    log(1)
    # 1

    mutate(df, b = .env$a + 1)

    mutate(df, b = .data[[a_var]] + 1)