Scala regards a method with the equals sign before the body as a function definition and a function always returns a value in functional programming.

Scala把主体之前的部分包含等于号作为函数定义，而一个函数在函数式编程中永远都有返回值。

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Note that for the single sign-on authentication to properly work, you must include a call to the authorizeCallback() method in your onActivityResult() function.

注意，为了单点登录身份认证正确工作，您必须在 onActivityResult() 函数中包含一个对 authorizeCallback() 方法的调用。

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Because semicolons, function return types, method arguments lists, and even the curly braces are sometimes omitted, using an equals sign prevents several possible parsing ambiguities.

因为分号，函数返回类型，方法参数列表，甚至大括号都经常会被省略，使用等于号可以避免几种可能的二义性。使用等于号也提醒了我们，即使是函数，在Scala里面也是值。

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