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How can I check for “undefined” in JavaScript? [duplicate]
.../ true
As @CMS pointed out, this has been patched in ECMAScript 5th ed., and undefined is non-writable.
if (window.myVar) will also include these falsy values, so it's not very robust:
false
0
""
NaN
null
undefined
Thanks to @CMS for pointing out that your third case - if (myVariable) can als...
Regex lookahead for 'not followed by' in grep
...head, which is what you're after, requires a more powerful tool than the standard grep. You need a PCRE-enabled grep.
If you have GNU grep, the current version supports options -P or --perl-regexp and you can then use the regex you wanted.
If you don't have (a sufficiently recent version of) GNU ...
How to get mouse position in jQuery without mouse-events?
...ve there's a way to query the mouse position, but you can use a mousemove handler that just stores the information away, so you can query the stored information.
jQuery(function($) {
var currentMousePos = { x: -1, y: -1 };
$(document).mousemove(function(event) {
currentMousePos.x = ...
How to debug a referenced dll (having pdb)
I have two solutions in my workspace, say A and B.
10 Answers
10
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Android Studio/Intellij Idea: “Table of Contents” for a class
I have been messing around with Android Studio and so far I like most of what I have seen. One thing that has been annoying me though is this lack of "Table of Contents" for a class. I apologize for not knowing exactly what to call it. But what I am referring to is the dropdown menu in eclipse that ...
How to use Git?
... I have zero experience with any kind of version control system. My understanding is somehow they make distribution of projects easier.
...
How to set JFrame to appear centered, regardless of monitor resolution? [closed]
...to not set it visible until AFTER you center it. This way it won't appear and then jump around. As long as you have packed the frame or set the dimensions before the code in this answer, you will be fine.
– Erick Robertson
Oct 9 '15 at 14:51
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Re-entrant locks in C#
...g on the same object. The recursive code effectively already has the lock and so can continue unhindered.
lock(object) {...} is shorthand for using the Monitor class. As Marc points out, Monitor allows re-entrancy, so repeated attempts to lock on an object on which the current thread already has ...
What's the difference between Html.Label, Html.LabelFor and Html.LabelForModel
What's the difference between @Html.Label() , @Html.LabelFor() and @Html.LabelForModel() methods?
4 Answers
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How to remove all white space from the beginning or end of a string?
How can I remove all white space from the beginning and end of a string?
6 Answers
6
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