Conditional execution with base pipe

tidyverse
1

I'm trying to conditionally execute logic within a pipeline. Any ideas how to do this with the basepipe?

library(tidyverse)

qc <- TRUE

cars_mag <- rownames_to_column(mtcars, var="model") %>%
  mutate(
    mpg_cat=case_when(
      mpg <= 15 ~ "terrible",
      mpg <= 20 ~ "okay",
      mpg <= 25 ~ "pretty good",
      TRUE ~ "awesome"
    )
  ) %>%
  {if(qc) assign("inspect1", ., envir=globalenv()) else .} %>%
  group_by(mpg_cat) %>%
  summarize(
    across(c(mpg, disp, hp), list(mean=mean, sum=sum))
  ) 

cars_bp <- rownames_to_column(mtcars, var="model") |>
  mutate(
    mpg_cat=case_when(
      mpg <= 15 ~ "terrible",
      mpg <= 20 ~ "okay",
      mpg <= 25 ~ "pretty good",
      TRUE ~ "awesome"
    )
  ) |>
  {if(qc) assign("inspect1basepipe", value=_, envir=globalenv()) else _} |>
  group_by(mpg_cat) |>
  summarize(
    across(c(mpg, disp, hp), list(mean=mean, sum=sum))
  ) 
#> Error in {: function '{' not supported in RHS call of a pipe (<text>:29:3)

Created on 2025-08-22 with reprex v2.1.1

2

Hi @StatSteph

cars_bp <- rownames_to_column(mtcars, var = "model") |>
  mutate(
    mpg_cat = case_when(
      mpg <= 15 ~ "terrible",
      mpg <= 20 ~ "okay",
      mpg <= 25 ~ "pretty good",
      TRUE ~ "awesome"
    )
  ) |>
  (\(x) if (qc) {
    assign("inspect1basepipe", x, envir = globalenv())
    x
  } else
    x)() |>
  group_by(mpg_cat) |>
  summarize(across(c(mpg, disp, hp), list(mean = mean, sum = sum)))

use an anonymous function.

1 Like