Bash：在 output 中重用 printf 变量

Question

是否可以在格式化中多次使用传递给printf的变量？

例如，使用这一行：

printf 'Hi %s, welcome to %s. %s is a great place to work. Thanks %s.' "John" "The Icecream Factory"

如何“重用” printf中的第一个和第二个变量？

我在想类似的事情：

printf 'Hi %s[1], welcome to %s[2]. %s[1] is a great place to work. Thanks %s[2].' "John" "The Icecream Factory"

...但显然不是这样。

所需 output

Hi John, welcome to The Icecream Factory. The Icecream Factory is a great place to work. Thanks John.

实际 output

Hi John, welcome to The Icecream Factory.  is a great place to work. Thanks .

工作环境为bash 20 中的 bash。

Answer 1

While I don't think it's possible using either the built-in bash implementation of printf or the freestanding GNU printf(1) program, if you can target zsh instead, its version of printf supports POSIX-style printf(3) argument indexing:

通常，转换规范按顺序应用于每个参数，但它们可以通过将%替换为%n$和*替换为*n$来明确指定要使用的第n个参数。 建议您不要将这种显式样式的引用与普通样式混合，并且此类混合 styles 的处理可能会在未来发生变化。

$ printf 'Hi %1$s, welcome to %2$s. %2$s is a great place to work. Thanks %1$s.\n' "John" "The Icecream Factory"
Hi John, welcome to The Icecream Factory. The Icecream Factory is a great place to work. Thanks John.