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Is there a way to avoid null check before the for-each loop iteration starts? [duplicate]
Every time I have to iterate over a collection I end up checking for null, just before the iteration of the for-each loop starts. Like this:
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Index (zero based) must be greater than or equal to zero
Hey I keep getting an error:
8 Answers
8
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How does one remove an image in Docker?
I'm running Docker under Vagrant under OS X 10.8.4 (Mountain Lion), and whenever I try to delete a saved image, I get an error:
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When do I use fabs and when is it sufficient to use std::abs?
I assume that abs and fabs are behaving different when using math.h . But when I use just cmath and std::abs , do I have to use std::fabs or fabs ? Or isn't this defined?
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Equivalent VB keyword for 'break'
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In both Visual Basic 6.0 and VB.NET you would use:
Exit For to break from For loop
Wend to break from While loop
Exit Do to break from Do loop
depending on the loop type. See Exit Statements for more details.
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How can I group by date time column without taking time into consideration
I have a bunch of product orders and I'm trying to group by the date and sum the quantity for that date. How can I group by the month/day/year without taking the time part into consideration?
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JSON.parse vs. eval()
My Spider Sense warns me that using eval() to parse incoming JSON is a bad idea. I'm just wondering if JSON.parse() - which I assume is a part of JavaScript and not a browser-specific function - is more secure.
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Saving image from PHP URL
...URL to my PC.
Let's say I have a page, http://example.com/image.php , holding a single "flower" image, nothing else. How can I save this image from the URL with a new name (using PHP)?
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Multiple file extensions in OpenFileDialog
How can I use multiple file extensions within one group using OpenFileDialog ?
I have Filter = "BMP|*.bmp|GIF|*.gif|JPG|*.jpg|PNG|*.png|TIFF|*.tiff"
and I want to create groups so JPG are *.jpg and *.jpeg, TIFF are *.tif and *.tiff and also 'All graphic types'? How can I do that?
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Calling dynamic function with dynamic number of parameters [duplicate]
I’m looking for a trick about this. I know how to call a dynamic, arbitrary function in JavaScript, passing specific parameters, something like this:
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