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Run Cron job every N minutes plus offset
...on
An * in the minute field is the same as 0-59/1 where 0-59 is the range and 1 is the step. The command will run at the first minute in the range (0), then at all successive minutes that are distant from the first by step (1), until the last (59).
Which is why */20 * * * * will run at 0 minutes, ...
What is the difference between `throw new Error` and `throw someObject`?
I want to write a common error handler which will catch custom errors thrown on purpose at any instance of the code.
9 Answ...
How can I delay a method call for 1 second?
...und this solution to be easier than performSelector when mixing straight C and ObjC
– Paul Slocum
Jul 17 '13 at 23:25
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Why does Python use 'magic methods'?
I've been playing around with Python recently, and one thing I'm finding a bit odd is the extensive use of 'magic methods', e.g. to make its length available, an object implements a method, def __len__(self) , and then it is called when you write len(obj) .
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How to disable an Android button?
I have created a layout that contains two buttons, Next and Previous. In between the buttons I'm generating some dynamic views. So when I first launch the application I want to disable the "Previous" button since there wont be any previous views. I also want to disable the "Next" button when there a...
Scala constructor overload?
...ary Constructors in Scala must either call the primary constructor (as in landon9720's) answer, or another auxiliary constructor from the same class, as their first action. They cannot simply call the superclass's constructor explicitly or implicitly as they can in Java. This ensures that the primar...
Focus-follows-mouse (plus auto-raise) on Mac OS X
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You can do it for Terminal.app by issuing the following command at the command line:
defaults write com.apple.Terminal FocusFollowsMouse -bool true
For X11 apps you can do this:
defaults write com.apple.x11 wm_ffm -bool true
In Snow Leopard, use this instead:
defaults write org...
Linq select objects in list where exists IN (A,B,C)
...ad of array for allowedStatus because HashSet's contains method is fastest and there'll be performance issues with array if it contains more than 1000 items. var allowedStatus = new HashSet<string> { "A", "B", "C" };
– Jay Shah
Nov 9 '18 at 18:14
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What is the most efficient string concatenation method in python?
... Guido. Although it is worth remembering also that this is an old article and it predates the existence of things like ''.join (although I guess string.joinfields is more-or-less the same)
On the strength of that, the array module may be fastest if you can shoehorn your problem into it. But ''.jo...
MySQL Creating tables with Foreign Keys giving errno: 150
...e the primary keys in 2 other tables, but I am getting an errno: 150 error and it will not create the table.
20 Answers
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