Executes a JavaScript function or predicate within the page’s context and returns the result. The function receives ‘arg’ as its first argument. Example: evaluate(functionOrPredicate: "() => document.title") Example with argument: evaluate(functionOrPredicate: "selector => document.querySelector(selector).innerText", arg: "#myElement") Returns the JSON representation of the function’s return value.

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Definition

evaluate(
  functionOrPredicate: String!
  arg: JSON
): JSON!

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Arguments

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functionOrPredicate

String! A string containing the JavaScript function or predicate to execute. Example: "() => ({ width: window.innerWidth, height: window.innerHeight })" Example: "element => element.tagName" (if an element is the context)

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arg

JSON An optional JSON serializable argument to pass to the function.

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Returns

JSON! The JSON scalar type represents JSON values as specified by ECMA-404.