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What is a NullReferenceException, and how do I fix it?
...variables, either by hovering the mouse over their names, opening a (Quick)Watch window or using the various debugging panels like Locals and Autos.
If you want to find out where the reference is or isn't set, right-click its name and select "Find All References". You can then place a breakpoint at ...
Is there a use-case for singletons with database access in PHP?
...e having 42 ctor params or require lots of setters you are doing it wrong. Watch the Clean Code Talks please. Sorry, if I cannot be bothered to explain this yet another time. Feel free to ask in the PHP chatroom for more info.
– Gordon
May 5 '12 at 19:26
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For-each over an array in JavaScript
...n of intent makes no sense to you, then you and your code may benefit from watching Crockford's lecture on Programming Style & Your Brain.)
It is now even better to use for..of!
There is a debate about whether for..of or forEach() are preferable:
For maximum browser support, for..of requires...
What characters can be used for up/down triangle (arrow without stem) for display in HTML?
... ⌗ VIEWDATA SQUARE
U+2318 ⌘ PLACE OF INTEREST SIGN
U+231A ⌚ WATCH
U+231B ⌛ HOURGLASS
U+2326 ⌦ ERASE TO THE RIGHT
U+2327 ⌧ X IN A RECTANGLE BOX
U+2328 ⌨ KEYBOARD
U+2329 〈 LEFT-POINTING ANGLE BRACKET
U+232A 〉 RIGHT-POINTING ANGLE BRACKET
U+232B ⌫ ERASE...
What are the differences between virtual memory and physical memory?
...some time, your RAM looks like this:
Cool. Now suppose you again resume watching Avatar in VLC. Its memory requirement will shoot up! But...there is no space left for it to grow, as Notepad is snuggled at its bottom. So, again, all processes has to move below until VLC has found sufficient space!...
How to run a program without an operating system?
...thon subset has been ported to run on BIOS / UEFI: https://www.youtube.com/watch?v=bYQ_lq5dcvM
It can be argued that firmwares are indistinguishable from OSes, and that firmware is the only "true" bare metal programming one can do.
As this CoreOS dev puts it:
The hard part
When you power up a PC, t...
SQL query return data from multiple tables
....
Part 2
Subqueries - what they are, where they can be used and what to watch out for
Cartesian joins AKA - Oh, the misery!
There are a number of ways to retrieve data from multiple tables in a database. In this answer, I will be using ANSI-92 join syntax. This may be different to a number of ...
Error TF30063: You are not authorized to access … \DefaultCollection
...ate to the TFS page and log out of the wrong account and log back in.
For me, the issue was caused by using another live-id to unlock a windows phone for development. Somehow the credentials got cached, it seems.
share
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Extract filename and extension in Bash
I want to get the filename (without extension) and the extension separately.
37 Answers
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Difference between “git add -A” and “git add .”
...shortcut for doing both of those.
You can test the differences out with something like this (note that for Git version 2.x your output for git add . git status will be different):
git init
echo Change me > change-me
echo Delete me > delete-me
git add change-me delete-me
git commit -m initial...