Dhall - 表达式与注释不匹配，应输入文本

问题描述

我正在使用 Dhall 1.39.0 并收到此错误：

Error: Expression doesn't match annotation

- Text
+ { … : … } (a record type)
[snip]

You or the interpreter annotated this expression:

[ file contents ] 

... with this type or kind:

↳ Text

... but the inferred type or kind of the expression is actually:

↳ { Sentences :
      List
        { Name : Text,Object : Text,Statement : Bool,Subject : Text,Verb : Text
        },Version : Text
  }

这是从 cat show-and-tell.dhall | ~/external-programs/bin/dhall --explain text 产生的。

请注意，我可以将相关的 dhall 文件加载到 dhall-golang 库中并使其正确呈现。所以我有点困惑。

这里有一个有点人为的示例文件：

let Sentence : Type  =
{
  Name : Text,Verb : Text,Statement : Bool
}
let information : Type = {
  Version : Text,Sentences : List Sentence
}


let all = ".+"

let answer : information =  {
    Version = "v1",Sentences =
    [ { Name = "s1",Subject = "bobross",Verb = "${all}",Object = "${all}",Statement = True
    },{ Name = "s2",Subject = "Everyone",Statement = False
    },{ Name = "s3",Subject = "picasso",Verb = "questions",Statement = True
    }
  ]
}
in answer

解决方法

dhall text 用于呈现 Text 类型的 Dhall 表达式的值（有点像，例如 -r 的 jq 选项）：

$ echo '"Foo"' | dhall text
Foo

相比

$ echo '"Foo"' | dhall
"Foo"

你的表达式类型为 Information;您只需要 dhall 本身。

$ cat show-and-tell.dhall | dhall
{ Sentences =
  [ { Name = "s1",Object = ".+",Statement = True,Subject = "bobross",Verb = ".+"
    },{ Name = "s2",Statement = False,Subject = "Everyone",{ Name = "s3",Subject = "picasso",Verb = "questions"
    }
  ],Version = "v1"
}