如何将填充长度指定为 Guile 格式的参数?
How to specify the padding length as an argument in Guile's format?
Guile 的格式可以填充参数:
(format #f "~5d" 123) ;; => " 123"
但是如何从参数中读取填充长度?
(format #f "~?d" 5 123) ;; => " 123"
因为它是由 Bash 的 printf 完成的:
printf "%*d" 5 123 ## => " 123"
如 Guile Reference Manual 中所述,您可以使用 v
参数。
v - The next function argument as the parameter. v stands for “variable”, a parameter can be calculated at runtime and included in the arguments. Upper case V can be used too.
例如:
(format #f "~vd" 5 123)
=> " 123"
Guile 的格式可以填充参数:
(format #f "~5d" 123) ;; => " 123"
但是如何从参数中读取填充长度?
(format #f "~?d" 5 123) ;; => " 123"
因为它是由 Bash 的 printf 完成的:
printf "%*d" 5 123 ## => " 123"
如 Guile Reference Manual 中所述,您可以使用 v
参数。
v - The next function argument as the parameter. v stands for “variable”, a parameter can be calculated at runtime and included in the arguments. Upper case V can be used too.
例如:
(format #f "~vd" 5 123)
=> " 123"