如何在調試時打印Swift結構的自定義說明，而沒有其他內容？

Question

說我有一個這樣的結構：

struct MyStruct: CustomStringConvertible {
    let myInt: Int
    let myString: String

    var description: String {
        return "my int is \(myInt),\nand my string is \"\(myString)\""
    }
}

從代碼中打印描述可以正常工作。

let myStruct = MyStruct(myInt: 3, myString: "hello")
print(myStruct)

這導致

my int is 3,
and my string is "hello"

當我想從調試器打印myStruct的描述時出現問題。 po myStruct結果在

▿ my int is 3,
and my string is "hello"
  - myInt : 3
  - myString : "hello"

顯式打印其描述也無濟於事，因為po myStruct.description導致

"my int is 3,\nand my string is \"hello\""

我認為這可能與CustomDebugStringConvertible ，所以我添加了以下代碼：

extension MyStruct: CustomDebugStringConvertible {
    var debugDescription: String {
        return description
    }
}

不幸的是，這根本不會改變任何結果。

有沒有辦法

my int is 3,
and my string is "hello"

在調試時從命令行打印？

Answer 1

(lldb) expression print(myStruct)
my int is 3,
and my string is "hello"

您可以定義自己的“命令”

(lldb) help command
The following subcommands are supported:

      alias   -- Allow users to define their own debugger command
                 abbreviations.  This command takes 'raw' input (no need to
                 quote stuff).
      delete  -- Allow the user to delete user-defined regular expression,
                 python or multi-word commands.
      history -- Dump the history of commands in this session.
      regex   -- Allow the user to create a regular expression command.
      script  -- A set of commands for managing or customizing script commands.
      source  -- Read in debugger commands from the file <filename> and execute
                 them.
      unalias -- Allow the user to remove/delete a user-defined command
                 abbreviation.