如何使用外部 scope 中的同名变量解构 Typescript 中的变量？

Question

I want to use the variable name username and don't know how to do so in the following code:

  myFunction = async (email: string, password?: string): Promise<boolean> => {
    let username
    if (password) {
      { username } = await this.getUsernameAndDate(email, password)
    } else {
      username = await this.getUsernameByEmail({ email })
    }
    return this.sendUsername({ username })
  }

My linter complains that { username } is unused:

unused expression, expected an assignment or function call (no-unused-expression)tslint(1)

Iss there a propper way to do this if I want to only use username everywhere?

Answer 1

You need to put the destructuring in parentheses:

({ username } = await this.getUsernameAndDate(email, password));

This is true for JS as well. If you were declaring (with let , const , etc) while destructuring, you wouldn't need the parentheses.

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