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How do I check if an object has a specific property in JavaScript?
...perty] or, even worse, x.key will give you completely misleading results.
It depends on what you're looking for. If you want to know if an object physically contains a property (and it is not coming from somewhere up on the prototype chain) then object.hasOwnProperty is the way to go. All modern br...
Will console.log reduce JavaScript execution performance?
...ugging feature console.log reduce JavaScript execution performance? Will it affect the speed of script execution in production environments?
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Do I need dependency injection in NodeJS, or how to deal with …?
I currently creating some experimental projects with nodejs. I have programmed a lot Java EE web applications with Spring and appreciated the ease of dependency injection there.
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Failed to allocate memory: 8
...today, when I tried to run an app in NetBeans on a 2.3.3 Android platform, it shows me that:
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Regex to check whether a string contains only numbers [duplicate]
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var reg = /^\d+$/;
should do it. The original matches anything that consists of exactly one digit.
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Why is === faster than == in PHP?
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Because the equality operator == coerces, or converts, the data type temporarily to see if it’s equal to the other operand, whereas === (the identity operator) doesn’t need to do any converting whatsoever and thus less work is done, whic...
Is jquery a javascript library or framework? [closed]
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A library. According to the homepage, and which I agree with.
A framework is something that usually forces a certain way of implementing a solution, whereas jQuery is just a tool to make implementing what you want to do easier.
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Choosing Java vs Python on Google App Engine
...especially support for Java bytecode regardless of the languages used to write that code. Which language will give better performance and more power? Please advise. Thank you!
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Does a foreign key automatically create an index?
... a constraint, a relationship between two tables - that has nothing to do with an index per se.
But it is a known fact that it makes a lot of sense to index all the columns that are part of any foreign key relationship, because through a FK-relationship, you'll often need to lookup a relating table...
Remove secure warnings (_CRT_SECURE_NO_WARNINGS) from projects by default in Visual Studio
...gs that come up when using functions like scanf(). I found that you can do it by adding a line in the project option or a #define _CRT_SECURE_NO_WARNINGS in the beginning of the code.
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