Swift Error：变量在其自己的初始值内使用

Question

When I'm initializing an instance of an entity I'm getting the error Variable used within its own initial value .

Here is the code throwing the error:

class func buildWordDefinition (word:String, language:Language, root:TBXMLElement) -> WordDefinition
    {
        let word = WordDefinition(word: word, language: language)

The error points at the word variable.

Here is the WordDefinition class:

class WordDefinition {
    let word: String
    let language: Language

    init(word: String, language:Language)
    {
        self.word = word
        self.language = language
    }
}

What does this error mean ?

Answer 1

You are declaring a constant named word , and trying to use the argument with the same name to initialize it. The compiler tries to use the just declared constant to assign its own initial value, instead of using the argument.

Answer 2

I have faced same error when missing out if while unwrapping the text .

By adding if resolved above issue.

Answer 3

You are redefining a constant word which has the same name as a parameter within your function

class func buildWordDefinition (word:String, language:Language, root:TBXMLElement) -> WordDefinition
{
    // same name as the parameter here
    let word = WordDefinition(word: word, language: language)
}

Answer 4

You have a function parameter called word in scope and you're trying to create a constant with the same name. Name your constant something other than word .