检测FParsec何时未解析所有输入

Question

如何在不解析所有输入的情况下检测FParsec解析器何时停止？

例如,以下解析器p在找到意外字符时停止d,并且不会继续解析输入的其余部分.

let test p str =
    match run p str with
    | Success(result, _, _)   -> printfn "Success: %A" result
    | Failure(errorMsg, s, _) -> printfn "Failure: %s %A" errorMsg s 

let str s = pstring s

let a = str "a" .>> spaces
let b = str "b" .>> spaces
let p = many (a <|> b)

test p "ab a  d bba  " // Success: ["a"; "b"; "a"]

Answer 1

有一个特殊的解析器eof对应$于正则表达式.

试试这个:

let p = many (a <|> b) .>> eof

这可确保解析器仅在输入完全耗尽时才能成功.