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delete a.x vs a.x = undefined
...a.x = undefined
means that a.hasOwnProperty("x") will still return true, and therefore, it will still show up in a for in loop, and in Object.keys()
delete a.x
means that a.hasOwnProperty("x") will return false
The way that they are the same is that you can't tell if a property exists by testi...
Is “argv[0] = name-of-executable” an accepted standard or just a common convention?
...always be the name of the executable? Or is this just a common convention and not guaranteed to be true 100% of the time?
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How do I diff the same file between two different commits on the same branch?
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For instance, to see the difference for a file "main.c" between now and two commits back, here are three equivalent commands:
$ git diff HEAD^^ HEAD main.c
$ git diff HEAD^^..HEAD -- main.c
$ git diff HEAD~2 HEAD -- main.c
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Is the ternary operator faster than an “if” condition in Java [duplicate]
... readable doesn't mean it matters, perse.
– Jon Egeland
Mar 16 '12 at 22:42
24
@Jon: Yes, it doe...
Which characters need to be escaped in HTML?
...d in XML. Inside of an element, this just includes the entity escape ampersand & and the element delimiter less-than and greater-than signs < >:
& becomes &
< becomes <
> becomes >
Inside of attribute values you must also escape the quote character you're ...
How to create nonexistent subdirectories recursively using Bash?
... script that will dump some databases into a nice/neat directory structure and I realized that I need to test to make sure that the directories exist before I create them. The code I have works, but it seems that there is a better way to do it. Any suggestions?
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How to initialise memory with new operator in C++?
I'm just beginning to get into C++ and I want to pick up some good habits. If I have just allocated an array of type int with the new operator, how can I initialise them all to 0 without looping through them all myself? Should I just use memset ? Is there a “C++” way to do it?
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Place a button right aligned
...from the normal document flow so they can overflow their parent's boundary and mess up the parent's height, the clear:both CSS takes care of that (as does overflow:hidden). Play around with the JSFiddle example I added to see how floating and clearing behave (you'll want to drop the overflow:hidden ...
How do I skip a match when using Ctrl+D for multiple selections in Sublime Text 2?
...bo until what you want to skip is highlighted. E.g. if you have 3 matches, and you want to skip the 2nd, first highlight the 1st, press CTRL+D to highlight the 2nd, THEN press the key combo to skip the 2nd match and highlight the 3rd. Help?
– Tyler Collier
Oct ...
What is the difference between id and class in CSS, and when should I use them? [duplicate]
Here I gave an id to the div element and it's applying the relevant CSS for it.
15 Answers
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