JavaScript Feature Reference: Generator Function Web Browser Support Test

1. Introduction

In this web page there are two web browser JavaScript feature support tests; 1.) a feature implementation test, and 2.) a feature capability test. First, the implementation test is run. The implementation test determines if the web browser recognizes the JavaScript generator function. The implementation test is a simple test for the presence of web browser support, and a definitive test for the absence of web browser support. If the web browser does not recognize the JavaScript generator function, the testing is stopped and the implementation test reports: Fail (no support): The web browser does not recognize the JavaScript generator function. The web browser does not support the JavaScript generator function.

If the web browser recognizes the JavaScript generator function, the capability test is run. The capability test determines if the web browser's implementation of the JavaScript generator function includes support for at least one generator function capability. The capability test is a more definitive, albeit not an all inclusive, test for the presence of web browser support. If the web browser's implementation of the JavaScript generator function includes support for the tested capability, the capability test reports: Pass (at least partial/possibly full support): The web browser recognizes the JavaScript generator function, and supports at least one generator function capability. The web browser at least partially/possibly fully supports the JavaScript generator function. Positive determination of full web browser support is beyond the scope of this test. If the web browser's implementation of the JavaScript generator function does not include support for the tested capability, the capability test reports: Pass/Fail (partial support): The web browser recognizes the JavaScript generator function, but does not support at least one generator function capability. The web browser partially supports the JavaScript generator function.

The web browser support test source code is shown in Section 2.1. The web browser support test source code is run in Section 2.2, which shows the web browser support test result.

1.1. Generator Function Web Browser Support

• Pass (at least partial/possibly full support): ED13+, FF36+, CH39+, OP26+.
• Fail (no support): IE11-, SF5.1.7-.

1.2. Abbreviations

• IE = Internet Explorer.
• ED = Edge Legacy 12 - 18 (EdgeHTML based) and Edge 79+ (Chromium based).
• FF = Firefox.
• SF = Safari.
• CH = Chrome.
• OP = Opera.

2. Generator Function Web Browser Support Test

2.1. Web Browser Support Test Source Code

<p id='testId'><b>Fail</b> (no support): The web browser does not recognize the JavaScript generator function. The web browser does not support the JavaScript generator function.</p><!-- Hard code Fail because web browser no support error stops JavaScript execution. -->

<script>
function* generatorFunctionDeclaration(){} // Generator function using function declaration syntax.
var generatorFunctionExpression = function*(param){}; // Generator function using function expression syntax.
objectLiteral = {
 generatorFunctionMethod: function*(param){} // Generator function using object method syntax.
};
// Call generator functions. Each call returns a Generator object which inherits prototype from Object and is an iterator.
var generatorObjectOne = generatorFunctionDeclaration();
var generatorObjectTwo = generatorFunctionExpression();
var generatorObjectThree = objectLiteral.generatorFunctionMethod();
if ((window.generatorObjectOne) && (window.generatorObjectTwo) && (window.generatorObjectThree)){
 var element = document.getElementById("testId");
 if ((typeof generatorObjectOne === "object") && Object.prototype.isPrototypeOf(generatorObjectOne) && generatorObjectOne[Symbol.iterator] && (typeof generatorObjectTwo === "object") && Object.prototype.isPrototypeOf(generatorObjectTwo) && generatorObjectTwo[Symbol.iterator] && (typeof generatorObjectThree === "object") && Object.prototype.isPrototypeOf(generatorObjectThree) && generatorObjectThree[Symbol.iterator]){
  element.innerHTML = "<b>Pass</b> (at least partial/possibly full support): The web browser recognizes the JavaScript generator function, and supports at least one generator function capability. The web browser at least partially/possibly fully supports the JavaScript generator function. Positive determination of full web browser support is beyond the scope of this test.";
 } else {
  element.innerHTML = "<b>Pass/Fail</b> (partial support): The web browser recognizes the JavaScript generator function, but does not support at least one generator function capability. The web browser partially supports the JavaScript generator function.";
 }
}
</script>

2.2. Web Browser Support Test Result

Fail (no support): The web browser does not recognize the JavaScript generator function. The web browser does not support the JavaScript generator function.

3. Resources And Additional Information

• JavaScript Feature Reference (learnwebcoding.com)