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How to check if a string is a valid date
I have a string: "31-02-2010" and want to check whether or not it is a valid date.
What is the best way to do it?
14 Answ...
How to write WinForms code that auto-scales to system font and dpi settings?
...t there that say "WinForms doesn't auto-scale to DPI/font settings well; switch to WPF." However, I think that is based on .NET 1.1; it appears they actually did a pretty good job of implementing auto-scaling in .NET 2.0. At least based on our research and testing so far. However, if some of you out...
What is the difference between pip and conda?
...ager for python packages. However, I saw the installation on IPython's website use conda to install IPython.
12 Answers
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What is the difference between null and undefined in JavaScript?
...ed
alert(typeof TestVar); //shows undefined
null is an assignment value. It can be assigned to a variable as a representation of no value:
var TestVar = null;
alert(TestVar); //shows null
alert(typeof TestVar); //shows object
From the preceding examples, it is clear that undefined and null are ...
Private vs Public in Cache-Control
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The only difference is that with Private you are not allowing proxies to cache the data that travels through them. In the end, it all boils down to the data contained in the pages/files you are sending.
For example, your ISP could have an invisible prox...
Ineligible Devices section appeared in Xcode 6.x.x
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With the release of Xcode 6.3.1, check first the Update 5
Verify that "iOS Deployment Target" is <= the version of your iDevice.
You find this option in "Build Settings" tab when you click on a target of your projec...
SQLAlchemy: cascade delete
I must be missing something trivial with SQLAlchemy's cascade options because I cannot get a simple cascade delete to operate correctly -- if a parent element is a deleted, the children persist, with null foreign keys.
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What is a mixin, and why are they useful?
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A mixin is a special kind of multiple inheritance. There are two main situations where mixins are used:
You want to provide a lot of optional features for a class.
You want to use one particular feature in a lot of different classes.
For an example of number one,...
How do you run JavaScript script through the Terminal?
...to run a C program make filename then ./ filename . How do you do this with .js files?
15 Answers
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How to make a SPA SEO crawlable?
...wlable by google based on google's instructions . Even though there are quite a few general explanations I couldn't find anywhere a more thorough step-by-step tutorial with actual examples. After having finished this I would like to share my solution so that others may also make use of it and poss...