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Checking if a key exists in a JavaScript object?
... testing whether a key exists. What if the key exists but the value is actually undefined?
var obj = { key: undefined };
obj["key"] !== undefined // false, but the key exists!
You should instead use the in operator:
"key" in obj // true, regardless of the actual value
If you want to check if a...
What is the use of hashCode in Java?
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Buckets aside, hashcode is a method that the object calls to determine the order to store each object in memory. If objects are equal, then their hashcode must also be equal. (converse of this statement is false)
– NoName
Jun 24 '17 at 6:1...
How to disallow temporaries
For a class Foo, is there a way to disallow constructing it without giving it a name?
10 Answers
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Why are empty catch blocks a bad idea? [closed]
...-catch , which people (including Jon Skeet) say empty catch blocks are a really bad idea? Why this? Is there no situation where an empty catch is not a wrong design decision?
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Looping over a list in Python
I have a list with sublists in it. I want to print all the sublists with length equal to 3.
4 Answers
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How to “re-run with -deprecation for details” in sbt?
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> compile
> exit
Due to in ThisBuild, set applies the settings to all sub-projects, as well.
Command Line
You could also run the above as a single command on command line.
sbt '; set scalacOptions in ThisBuild ++= Seq("-unchecked", "-deprecation") ; compile'
The trick is to use ; (sem...
Remove menu and status bars in TinyMCE 4
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Small typo: menuBar: 'file edit' should be menubar: 'file edit'
– Cory Mawhorter
May 27 '13 at 9:49
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ipython notebook clear cell output in code
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Using the clear_output(wait=True) will generally make the result nicer if you have clear_output inside a loop.
– Toke Faurby
Jun 8 '17 at 23:49
1
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Security of REST authentication schemes
...s answer only mentioned SSL in the context of data transfer and didn't actually cover authentication.
You're really asking about securely authenticating REST API clients. Unless you're using TLS client authentication, SSL alone is NOT a viable authentication mechanism for a REST API. SSL without ...
RSpec controller testing - blank response.body
...with a problem when testing my controllers with RSpec - the response.body call always returns an empty string. In browser everything renders correctly, and cucumber feature tests seem to get it right, but RSpec fails each and every time.
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