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Python `if x is not None` or `if not x is None`?
I've always thought of the if not x is None version to be more clear, but Google's style guide and PEP-8 both use if x is not None . Is there any minor performance difference (I'm assuming not), and is there any case where one really doesn't fit (making the other a clear winner for my convent...
Is it safe to remove selected keys from map within a range loop?
How can one remove selected keys from a map?
Is it safe to combine delete() with range, as in the code below?
4 Answers
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How to fix Array indexOf() in JavaScript for Internet Explorer browsers
If you have worked with JavaScript at any length you are aware that Internet Explorer does not implement the ECMAScript function for Array.prototype.indexOf() [including Internet Explorer 8]. It is not a huge problem, because you can extend the functionality on your page with the following code.
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Aggregate function in an SQL update query?
I'm trying to set the value in one table to the sum of the values in another table. Something along these lines:
6 Answers...
Prevent automatic browser scroll on refresh
If you go to a page a and scroll around then refresh the page will refresh at the spot where you left it. This is great, however this also occurs on pages where there is a anchor location in the url. An example would be if you clicked on a link http://example.com/post/244#comment5 and refreshed th...
PHP random string generator
I'm trying to create a randomized string in PHP, and I get absolutely no output with this:
59 Answers
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How to compare types
Quick question: how to compare a Type type (pun not intended) with another type in C#?
I mean, I've a Type typeField and I want to know if it is System.String , System.DateTime , etc., but typeField.Equals(System.String) doesn't work.
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Margin while printing html page
I am using a separate style-sheet for printing. Is it possible to set right and left margin in the style-sheet which set the print margin (i.e. margin on paper).
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How can I change Mac OS's default Java VM returned from /usr/libexec/java_home
(Wasn't sure if this should go on SU... migration is certainly an option, but more programmers read questions here, so here goes).
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Remove the image from a imageview Android [duplicate]
I'm trying to make an ImageView that holds a gallery of images. By touching the user request to load the next image. If the next image isn't found in the server or takes time to load I need the old image to be empty.
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