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JavaScript private methods
... every object instance, it creates a separate function bound to the object and not the class. Also, this does not get garbage collected until the object itself is destroyed.
– Arindam
Feb 6 '12 at 22:37
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MySQL, Check if a column exists in a table with SQL
... query that will check if a specific table in MySQL has a specific column, and if not — create it. Otherwise do nothing. This is really an easy procedure in any enterprise-class database, yet MySQL seems to be an exception.
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Overflow-x:hidden doesn't prevent content from overflowing in mobile browsers
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Creating a site wrapper div inside the <body> and applying the overflow-x:hidden to the wrapper instead of the <body> or <html> fixed the issue.
It appears that browsers that parse the <meta name="viewport"> tag simply ignore overflow attributes on t...
Deleting queues in RabbitMQ
... about the data in management database; i.e. users, vhosts, messages etc., and neither about other queues, then you can reset via commandline by running the following commands in order:
WARNING: In addition to the queues, this will also remove any users and vhosts, you have configured on your Ra...
How to decide font color in white or black depending on background color?
...need to break the hex code into 3 pieces to get the individual red, green, and blue intensities. Each 2 digits of the code represent a value in hexadecimal (base-16) notation. I won't get into the details of the conversion here, they're easy to look up.
Once you have the intensities for the individ...
How can I create an Asynchronous function in Javascript?
...iscussing this with a friend yesterday so this answer is perfect! I understand and can identify the async functions and use them in JS properly. But simply why can't we implement custom ones is not clear to me. It's like a black box that we know how make it work (using, say, setInterval) but that we...
What are the differences between poll and select?
I am referring to the POSIX standard select and poll system C API calls.
3 Answers
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Are custom elements valid HTML5?
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The Custom Elements specification is available in Chrome and Opera, and becoming available in other browsers. It provides a means to register custom elements in a formal manner.
Custom elements are new types of DOM elements that can be defined by
authors. Unlike decorators, which ...
Break promise chain and call a function based on the step in the chain where it is broken (rejected)
...et's say you have something like the following:
stepOne()
.then(stepTwo, handleErrorOne)
.then(stepThree, handleErrorTwo)
.then(null, handleErrorThree);
To better understand what's happening, let's pretend this is synchronous code with try/catch blocks:
try {
try {
try {
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Cookies on localhost with explicit domain
...sic thing about cookies. On localhost, when I set a cookie on server side and specify the domain explicitly as localhost (or .localhost). the cookie does not seem to be accepted by some browsers.
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