大约有 40,000 项符合查询结果(耗时:0.0564秒) [XML]

https://stackoverflow.com/ques... 

What's the difference between using “let” and “var”?

...does not create a property on the global object: var foo = "Foo"; // globally scoped let bar = "Bar"; // globally scoped console.log(window.foo); // Foo console.log(window.bar); // undefined Redeclaration In strict mode, var will let you re-declare the same variable in the same scope while let...
https://stackoverflow.com/ques... 

How to understand nil vs. empty vs. blank in Ruby

...s the negation of .blank?. Array gotcha: blank? will return false even if all elements of an array are blank. To determine blankness in this case, use all? with blank?, for example: [ nil, '' ].blank? == false [ nil, '' ].all? &:blank? == true ...
https://stackoverflow.com/ques... 

Get elements by attribute when querySelectorAll is not available without using libraries?

... and returns only those elements with a "data-foo" attribute: function getAllElementsWithAttribute(attribute) { var matchingElements = []; var allElements = document.getElementsByTagName('*'); for (var i = 0, n = allElements.length; i < n; i++) { if (allElements[i].getAttribute(attri...
https://stackoverflow.com/ques... 

Best/Most Comprehensive API for Stocks/Financial Data [closed]

... not sure if it is documented or not, but this code sample should showcase all of the features (namely the stat types [parameter f in the query string]. I'm sure you can find documentation (official or not) if you search for it. http://www.goldb.org/ystockquote.html Edit I found some unofficial ...
https://stackoverflow.com/ques... 

What do all of Scala's symbolic operators mean?

...se of teaching, into four categories: Keywords/reserved symbols Automatically imported methods Common methods Syntactic sugars/composition It is fortunate, then, that most categories are represented in the question: -> // Automatically imported method ||= // Syntactic sugar ++= // Syn...
https://stackoverflow.com/ques... 

What should I use Android AccountManager for?

.../ Alarm only available from API >= 7 (this doesn't matter anymore) Finally, if you use a SyncAdapter, seriously consider Firebase Cloud Messaging (previously Google Cloud Messaging) aka "push notifications" to have fresher updates and optimized battery usage. ...
https://stackoverflow.com/ques... 

What are some (concrete) use-cases for metaclasses?

...a couple functions I found that I was able to increment the figure count, call draw manually, etc, but I needed to do these before and after every plotting call. So to create both an interactive plotting wrapper and an offscreen plotting wrapper, I found it was more efficient to do this via metacla...
https://stackoverflow.com/ques... 

Is it ever advantageous to use 'goto' in a language that supports loops and functions? If so, why?

...o this already): Cleanly exiting a function Often in a function, you may allocate resources and need to exit in multiple places. Programmers can simplify their code by putting the resource cleanup code at the end of the function, and all "exit points" of the function would goto the cleanup label....
https://stackoverflow.com/ques... 

What is the purpose of the -m switch?

Could you explain to me what the difference is between calling 3 Answers 3 ...
https://stackoverflow.com/ques... 

How to get the value from the GET parameters?

...ist of browser support see here. https://developer.mozilla.org/en-US/docs/Web/API/URLSearchParams https://developer.mozilla.org/en-US/docs/Web/API/URL/URL https://url.spec.whatwg.org/ Eric Bidelman, an engineer at Google, recommends using this polyfill for unsupported browsers. ...