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How to check if an object is an array?
...Array.isArray(obj)
(Supported by Chrome 5, Firefox 4.0, IE 9, Opera 10.5 and Safari 5)
For backward compatibility you can add the following
# only implement if no native implementation is available
if (typeof Array.isArray === 'undefined') {
Array.isArray = function(obj) {
return Object.pr...
Inserting a Link to a Webpage in an IPython Notebook
...e, certain special characters like "(" or ")" may brake the file/page path and lead to the link not working. I fixed it by replacing them with the code equivalents found here and then everything worked. theukwebdesigncompany.com/articles/entity-escape-characters.php
– Afflatus
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mongodb: insert if not exists
...-find-else-update block entirely. It will insert if the key doesn't exist and will update if it does.
Before:
{"key":"value", "key2":"Ohai."}
After:
{"key":"value", "key2":"value2", "key3":"value3"}
You can also specify what data you want to write:
data = {"$set":{"key2":"value2"}}
Now yo...
Memory management in Qt?
I'm quite new to Qt and am wondering on some basic stuff with memory management and the life of objects. When do I need to delete and/or destroy my objects? Is any of this handled automatically?
...
Laravel redirect back to original destination after login
This seems like a pretty basic flow, and Laravel has so many nice solutions for basic things, I feel like I'm missing something.
...
jQuery select all except first
... all but the first of an element? So in the following code only the second and third element would be accessed. I know I can access them manually but there could be any number of elements so thats not possible. Thanks.
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How to check whether a variable is a class or not?
...k is redundant. If it didn't there would be no way to instantiate whatever and thus you couldn't perform the check in the first place.
– a_guest
Dec 16 '16 at 12:42
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Function vs. Stored Procedure in SQL Server
I've been learning Functions and Stored Procedure for quite a while but I don't know why and when I should use a function or a stored procedure. They look same to me, maybe because I am kinda newbie about that.
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Is there a “not in” operator in JavaScript for checking object properties?
...se statement just to use the else portion...
Just negate your condition, and you'll get the else logic inside the if:
if (!(id in tutorTimes)) { ... }
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Check if directory mounted with bash
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Running the mount command without arguments will tell you the current mounts. From a shell script, you can check for the mount point with grep and an if-statement:
if mount | grep /mnt/md0 > /dev/null; then
echo "yay"
else
echo "nay"
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