如何在R中无函数跨行拼接长字符串且不引入换行符？

问题背景 #

需要编写超出显示宽度的长字符串，希望拆分为多行书写以提升可读性，且最终字符串不含换行符。目前使用paste0()实现，但想寻找无需调用函数的原生方法。

当前可行方案（使用paste0()） #

long_string <- paste0(
  "This is a very long string that I would like to split across ",
  "multiple lines without introducing any new line characters in ",
  "the final output. This makes the code more readable without ",
  "affecting the string's integrity."
)

long_string
#> [1] "This is a very long string that I would like to split across multiple lines without introducing any new line characters in the final output. This makes the code more readable without affecting the string's integrity."

尝试过的无效方法 #

直接在字符串内换行 #

最终字符串会插入换行符\n，不符合需求：

long_string <- "This is a very long string that I would like to split across 
multiple lines without introducing any new line characters in 
the final output. This makes the code more readable without 
affecting the string's integrity."

long_string
#> [1] "This is a very long string that I would like to split across \nmultiple lines without introducing any new line characters in \nthe final output. This makes the code more readable without \naffecting the string's integrity."

使用&拼接 #

R不支持该操作，会报错：

long_string <- "This is a very long string that I would like to split across " &
  "multiple lines without introducing any new line characters in " &
  "the final output. This makes the code more readable without " &
  "affecting the string's integrity."
#> Error in "This is a very long string that I would like to split across " & : operations are possible only for numeric, logical or complex types

long_string
#> Error in eval(expr, envir, enclos): object 'long_string' not found

每行单独写带引号的字符串 #

仅首个子串会被存入变量，其余为独立输出的字符串：

long_string <- "This is a very long string that I would like to split across "
"multiple lines without introducing any new line characters in "
#> [1] "multiple lines without introducing any new line characters in "
"the final output. This makes the code more readable without "
#> [1] "the final output. This makes the code more readable without "
"affecting the string's integrity."
#> [1] "affecting the string's integrity."

print(long_string)
#> [1] "This is a very long string that I would like to split across "

使用\换行 #

最终字符串仍保留换行符，不符合需求：

long_string <- "This is a very long string that I would like to split across \
multiple lines without introducing any new line characters in \
the final output. This makes the code more readable without \
affecting the string's integrity."

long_string
#> [1] "This is a very long string that I would like to split across \nmultiple lines without introducing any new line characters in \nthe final output. This makes the code more readable without \naffecting the string's integrity."

答案 #

R没有无需调用函数就能跨行拼接字符串且最终结果不含换行符的原生语法。

不过可以用一些更简洁的替代方式：

1. 简化paste0()写法：利用R的向量特性，将所有字符串放入一个向量中传递：

long_string <- paste0(c(
  "This is a very long string that I would like to split across ",
  "multiple lines without introducing any new line characters in ",
  "the final output. This makes the code more readable without ",
  "affecting the string's integrity."
))

2. 使用paste()的collapse参数（效果与paste0一致）：

long_string <- paste(c(
  "This is a very long string that I would like to split across ",
  "multiple lines without introducing any new line characters in ",
  "the final output. This makes the code more readable without ",
  "affecting the string's integrity."
), collapse = "")

3. 自定义简短函数（适合频繁使用场景）：

str_join <- function(...) paste0(...)

long_string <- str_join(
  "This is a very long string that I would like to split across ",
  "multiple lines without introducing any new line characters in ",
  "the final output. This makes the code more readable without ",
  "affecting the string's integrity."
)

内容的提问来源于stack exchange，提问作者Tripartio