將變量名作為參數從外部函數傳遞到 R 中的內部函數的問題？

Question

我試圖自動化的過程，創造一個外部函數運行幾個較小的內部功能，但是function有variable names作為參數是導致錯誤：

當我自己運行下面的函數時，它工作正常：

gapminder <- read.csv("https://raw.githubusercontent.com/swcarpentry/r-novice-gapminder/gh-pages/_episodes_rmd/data/gapminder-FiveYearData.csv")

################ fn_benchmark_country ################

fn_benchmark_country  <- function(bench_country = India){
  
  bench_country = enquo(bench_country)

  gapminder_benchmarked_wider <- gapminder %>% 
                                  select(country, year, gdpPercap) %>% 
                                  pivot_wider(names_from = country, values_from = gdpPercap) %>% 
                                  arrange(year) %>% 
                                  
                                  mutate(across(-1, ~ . - !!bench_country))
                                  
  # Reshaping back to Longer
  gapminder_benchmarked_longer <- gapminder_benchmarked_wider %>% 
                                  pivot_longer(cols = !year, names_to = "country", values_to = "benchmarked") 
 
  # Joining tables
  gapminder_joined <- left_join(x = gapminder, y = gapminder_benchmarked_longer, by = c("year","country"))

  # converting to factor
  gapminder_joined$country <- as.factor(gapminder_joined$country)
  
  return(gapminder_joined)  
}

################ ----------------------------- ################

# Calling function
fn_benchmark_country(Vietnam) 

country     year     pop  continent  lifeExp    gdpPercap   benchmarked

Afghanistan 1952    8425333 Asia    28.80100    779.4453    232.879565
Afghanistan 1957    9240934 Asia    30.33200    820.8530    230.791034

但是當我在外部函數中運行它時，它給了我錯誤：

fn_run_all <-function(bench_country = India, year_start = 1952, year_end = 2007){
  
  bench_country = bench_country
  year_start = year_start
  year_end = year_end
  
  fn_benchmark_country(bench_country)
}

fn_run_all()

Error in fn_run_all() : object 'India' not found

如果我將enquo添加到參數中，那么我仍然會收到如下所示的錯誤”

fn_run_all <-function(bench_country = India, year_start = 1952, year_end = 2007){
  
  bench_country = enquo(bench_country)
  year_start = year_start
  year_end = year_end
  
  fn_benchmark_country(bench_country)
}

fn_run_all()

Error: Problem with `mutate()` input `..1`. x Base operators are not defined for quosures. Do you need to unquote the quosure? # Bad: lhs - myquosure # Good: lhs - !!myquosure i Input `..1` is `across(-1, ~. - bench_country)`.

不知道如何解決這個問題，將不勝感激任何幫助！

從這里添加新的相關問題

現在由於上次內部函數調用fn_create_plot()而出現錯誤

由於使用bench_country creating dynamic subtitle情節的creating dynamic subtitle ，因此發生了相同類型的問題，但這次我使用了{{}}但仍然遇到問題

fn_run_all <-function(bench_country = India, year_start = 1952, year_end = 2007){
  

  year_start = year_start
  year_end = year_end
  
  fn_benchmark_country({{bench_country}})
  
  fn_year_filter(gapminder_joined, year_start, year_end) %>% 
  
  fn_create_plot(., year_start, year_end, {{bench_country}})
}

fn_run_all(Vietnam, 1967, 2002)

Error in sprintf("Benchmarked %i in blue line \nFor Countries with pop > 30000000 \n(Chart created by ViSa)", : object 'Vietnam' not found

功能代碼參考

################ fn_create_plot ################
  
fn_create_plot <- function(df, year_start, year_end, bench_country ){

                  
                  
                  # plotting
                      ggplot(df) +
                        
                      geom_vline(xintercept = 0, col = "blue", alpha = 0.5) +
    
                      geom_label( label="India - As Benchamrking line", x=0, y="United States",
                        label.padding = unit(0.55, "lines"), # Rectangle size around label
                        label.size = 0.35, color = "black") +
                      
                      geom_segment(aes(x = benchmarked_start, xend = benchmarked_end,
                                       y = country, yend = country,
                                       col = continent), alpha = 0.5, size = 7) +
                      
                      geom_point(aes(x = benchmarked, y = country, col = continent), size = 9, alpha = .6) +
                      
                      geom_text(aes(x = benchmarked_start + 8, y = country,
                                    label = paste(country, round(benchmarked_start))),
                                col = "grey50", hjust = "right") +
                      
                      geom_text(aes(x = benchmarked_end - 4.0, y = country,
                                    label = round(benchmarked_end)),
                                col = "grey50", hjust = "left") +
                    
                      
                      # scale_x_continuous(limits = c(20,85)) +
                      
                      scale_color_brewer(palette = "Pastel2") +
                      
                      labs(title = sprintf("GdpPerCapita Differenece with India (Starting point at %i and Ending at %i)",year_start, year_end),
                           subtitle = sprintf("Benchmarked %i in blue line \nFor Countries with pop > 30000000 \n(Chart created by ViSa)", bench_country),
                           col = "Continent", x = sprintf("GdpPerCap Difference at %i & %i", year_start, year_end) ) +
                      
                  # background & theme settings
                      theme_classic() +
                      
                      theme(legend.position = "top", 
                            axis.line = element_blank(),
                            axis.ticks = element_blank(),
                            axis.text = element_blank()
                            )
}

################ ----------------------------- ################

Answer 1

當您使用enquo()您還需要使用!! 當您在函數內調用相關變量時。 這有效：

fn_run_all <-function(bench_country = India, year_start = 1952, year_end = 2007){
  
  bench_country = enquo(bench_country)
  year_start = year_start
  year_end = year_end
  
  fn_benchmark_country(!! bench_country)
}

fn_run_all()

您也可以只替換enquo()和!! 使用隧道{{ }} ：

fn_run_all <-function(bench_country = India, year_start = 1952, year_end = 2007){
  
  year_start = year_start
  year_end = year_end
  
  fn_benchmark_country({{ bench_country }})
}

fn_run_all()