readformat

format!(). 的逆操作。格式参数是格式字符串，s 参数是要匹配的字符串。

示例

• readf1("Hello, {}!", "Hello, world!") => Some("world")
• readf("I hope {} are {}!", "I hope you are doing well!") => Some(vec!["you", "well"])
• readf1("Goodbye, {}!", "Hello, world!") => None