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typeof !== “undefined” vs. != null
...gument, or as a global variable), I think the best way to do it is:
if (my_variable === undefined)
jQuery does it, so it's good enough for me :-)
Otherwise, you'll have to use typeof to avoid a ReferenceError.
If you expect undefined to be redefined, you could wrap your code like this:
(functi...
PostgreSQL naming conventions
.... Postgresql treats identifiers case insensitively when not quoted (it actually folds them to lowercase internally), and case sensitively when quoted; many people are not aware of this idiosyncrasy. Using always lowercase you are safe. Anyway, it's acceptable to use camelCase or PascalCase (or UPPER...
How to get Maven project version to the bash command line
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I'm removing all logging (INFO,WARNING,etc) and 'Download' messages with mvn org.apache.maven.plugins:maven-help-plugin:2.1.1:evaluate -Dexpression=project.version|grep -Ev '(^\[|Download\w+:)'
– Chadwick
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Is it acceptable and safe to run pip install under sudo?
...ns together will get me back on track :)
– markwalker_
Feb 22 '13 at 16:40
1
also, for installing...
What are all the common undefined behaviours that a C++ programmer should know about? [closed]
What are all the common undefined behaviours that a C++ programmer should know about?
11 Answers
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Make anchor link go some pixels above where it's linked to
... window.scrollTo(window.scrollX, window.scrollY - 100);
});
This will allow the browser to do the work of jumping to the anchor for us and then we will use that position to offset from.
EDIT 1:
As was pointed out by @erb, this only works if you are on the page while the hash is changed. Enter...
What are the differences between struct and class in C++?
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That's not really a second difference, it's just that the question stated the difference incompletely. All subobjects are private by default when using the class, public by default with struct, and both define a class type.
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What is the preferred syntax for defining enums in JavaScript?
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This isn't much of an answer, but I'd say that works just fine, personally
Having said that, since it doesn't matter what the values are (you've used 0, 1, 2), I'd use a meaningful string in case you ever wanted to output the current value.
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Does the 'mutable' keyword have any purpose other than allowing the variable to be modified by a con
...able of a class with the mutable keyword. As far as I can see it simply allows you to modify a variable in a const method:
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Java / Android - How to print out a full stack trace?
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There's overrides of all the log methods with (String tag, String msg, Throwable tr) signatures.
Passing an exception as the third parameter should give you the full stacktrace in logcat.
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