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How to delete items from a dictionary while iterating over it?
...--------------------------------------------------
Traceback (most recent call last):
File "<ipython console>", line 1, in <module>
RuntimeError: dictionary changed size during iteration
As stated in delnan's answer, deleting entries causes problems when the iterator tries to move on...
Get difference between 2 dates in JavaScript? [duplicate]
...day. As for always returning a positive number, that was a feature :) Typically when one talks about the number of days between two dates, that number is positive. If direction matters, just remove the Math.abs().
– TNi
Jul 11 '10 at 22:38
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Check if a value is an object in JavaScript
...o examine variable's properties, but it is not a bulletproof recipe (after all there's no recipe at all!) for checking whether it's an object, far from it. Since people tend to look for something to copy from here without doing any research, I'd highly recommend that they turn to the other, most upv...
How to get the width and height of an android.widget.ImageView?
...eight, finalWidth;
final ImageView iv = (ImageView)findViewById(R.id.scaled_image);
final TextView tv = (TextView)findViewById(R.id.size_label);
ViewTreeObserver vto = iv.getViewTreeObserver();
vto.addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
public boolean onPreDraw() {
...
indexOf method in an object array?
... think to see the performance of this method vs. a simple for loop. Especially when you're running on a mobile platform with limited resources.
– Doug
Aug 17 '15 at 5:51
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How to concatenate strings in twig
...like Alessandro said, and here it is in the documentation:
~: Converts all operands into strings and concatenates them. {{ "Hello
" ~ name ~ "!" }} would return (assuming name is 'John') Hello John!. – http://twig.sensiolabs.org/doc/templates.html#other-operators
And here is an example so...
How to check if object has any properties in JavaScript?
...d Apr 20 '10 at 6:49
Daniel VassalloDaniel Vassallo
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Entity Framework 6 Code first Default value
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You can do it by manually edit code first migration:
public override void Up()
{
AddColumn("dbo.Events", "Active", c => c.Boolean(nullable: false, defaultValue: true));
}
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Difference between variable declaration syntaxes in Javascript (including global variables)?
...here are a couple of differences, though in practical terms they're not usually big ones.
There's a fourth way, and as of ES2015 (ES6) there's two more. I've added the fourth way at the end, but inserted the ES2015 ways after #1 (you'll see why), so we have:
var a = 0; // 1
let a = 0; // 1...
How to check if a Unix .tar.gz file is a valid file without uncompressing?
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What about just getting a listing of the tarball and throw away the output, rather than decompressing the file?
tar -tzf my_tar.tar.gz >/dev/null
Edited as per comment. Thanks zrajm!
Edit as per comment. Thanks Frozen Flame! This test in no way implies integrity ...