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A positive lambda: '+[]{}' - What sorcery is this? [duplicate]
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Yes, the code is standard conforming. The + triggers a conversion to a plain old function pointer for the lambda.
What happens is this:
The compiler sees the first lambda ([]{}) and generates a closure object according to §5.1.2. As the lambda...
How to include JavaScript file or library in Chrome console?
... To extend Harman's answer, I wrapped it around a JS function and use it as follows ... var _loadScript = function(path){ var script= document.createElement('script'); script.type= 'text/javascript'; script.src= path; document.head.appendChild(script); } _loadScript('documentcloud...
Create a tar.xz in one command
I am trying to create a .tar.xz compressed archive in one command. What is the specific syntax for that?
5 Answers
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Is it possible to download an old APK for my app from Google Play?
...isions to my app. Unfortunately, I didn't keep copies of all the old APKs, and now I'd like to test upgrade from the old versions to my new version. Is there any way to download Google's copy of my old versions? The Google Play developer console shows my old APKs, but without a download link. I trie...
What is the !! (not not) operator in JavaScript?
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This is used to convert truthy values to boolean true, and falsy values too boolean false.
– thetoolman
Jul 16 '12 at 3:53
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How do you delete a column by name in data.table?
...the following will remove column foo from the data.table df3:
# Method 1 (and preferred as it takes 0.00s even on a 20GB data.table)
df3[,foo:=NULL]
df3[, c("foo","bar"):=NULL] # remove two columns
myVar = "foo"
df3[, (myVar):=NULL] # lookup myVar contents
# Method 2a -- A safe idiom for excl...
Python OpenCV2 (cv2) wrapper to get image size?
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cv2 uses numpy for manipulating images, so the proper and best way to get the size of an image is using numpy.shape. Assuming you are working with BGR images, here is an example:
>>> import numpy as np
>>> import cv2
>>> img = cv2.imread('foo.jpg')
&g...
Showing a different background colour in Vim past 80 characters
...n Vim window open with the leftmost 80 columns using the normal background and anything past that using a slightly different background. The Vim window background should be a different color, not just text that goes over the 80 character point. This would indicate how close I am getting to the 80-ch...
How can I brew link a specific version?
...oo like /usr/local/Cellar/libfoo/1.0.1 , /usr/local/Cellar/libfoo/HEAD and /usr/local/Cellar/libfoo/mycopy
5 Answers
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What's the proper value for a checked attribute of an HTML checkbox?
...d="blue">
<input name=name id=id type=checkbox checked="false">
And only the following will be unchecked:
<input name=name id=id type=checkbox>
See also this similar question on disabled="disabled".
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