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How to check a not-defined variable in JavaScript
...at don't exist, undefined. The DOM returns null for almost all cases where it fails to find some structure in the document, but in JavaScript itself undefined is the value used.
Second, no, there is not a direct equivalent. If you really want to check for specifically for null, do:
if (yourvar ===...
Unit testing Anti-patterns catalogue
...resent to formally distinguish an actual anti-pattern from a simple bad habit, bad practice, or bad idea:
31 Answers
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How do I create and access the global variables in Groovy?
...scoping can be different than expected. That is because a Groovy script in itself is a class with a method that will run the code, but that is all done runtime. We can define a variable to be scoped to the script by either omitting the type definition or in Groovy 1.8 we can add the @Field annotatio...
Measure and Benchmark Time for Ruby Methods
...nd the time taken for database access and redis access. I do not want to write Benchmark.measure before every statement. Does the ruby interpreter gives us any hooks for doing this ?
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How do I replace whitespaces with underscore?
I want to replace whitespace with underscore in a string to create nice URLs. So that for example:
13 Answers
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How to log SQL statements in Grails
...rue
}
in DataSource.groovy (as per these instructions) was enough to get it working in my environment. It seems that parts of the FAQ are out of date (e.g. "the many-to-many columns backwards" question) so this might also be something that changed in the meantime.
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Disable single warning error
Is there a way to disable just a single warning line in a cpp file with visual studio?
11 Answers
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What is the largest TCP/IP network port number allowable for IPv4?
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The port number is an unsigned 16-bit integer, so 65535.
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Git - How to close commit editor?
I'm new to git and learning from a PDF.
I just executed a command $ git commit and it opens a new editor. But I'm trying to close that new commit editor. How to do this? I'm using git on windows.
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test if event handler is bound to an element in jQuery [duplicate]
Is it possible to determine whether an element has a click handler, or a change handler, or any kind of event handler bound to it using jQuery?
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