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What does “Object reference not set to an instance of an object” mean? [duplicate]
I am receiving this error and I'm not sure what it means?
8 Answers
8
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Is there a way to 'uniq' by column?
...eed the ,1 in -k1,1? why not just -k1?
– hello_there_andy
Nov 24 '14 at 20:10
19
@hello_there_and...
Is there a CSS selector for the first direct child only?
... you posted literally means "Find any divs that are inside of section divs and are the first child of their parent." The sub contains one tag that matches that description.
It is unclear to me whether you want both children of the main div or not. If so, use this:
div.section > div
If you onl...
What is the difference between Ruby 1.8 and Ruby 1.9
...m not clear on the differences between the "current" version of Ruby (1.8) and the "new" version (1.9). Is there an "easy" or a "simple" explanation of the differences and why it is so different?
...
While loop to test if a file exists in bash
... using a Bash (or related) shell by typing 'echo $SHELL'. I think that CSH and TCSH use a slightly different semantic for this loop.
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Computed read-only property vs function in Swift
...operties for just that: properties; meaning simple values that you can get and/or set. I use functions (or methods) when actual work is being done. Maybe something has to be computed or read from disk or from a database: In this case I use a function, even when only a simple value is returned. That ...
How do I implement __getattribute__ without an infinite recursion error?
...
..and do I want to always use object? What if I inherit from other classes?
– Greg
Dec 16 '08 at 16:29
1
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How to attach debugger to iOS app after launch?
I have an issue I am troubleshooting which occurs very infrequently and doesn't seem to happen when I have things running under Xcode.
...
Installing pip packages to $HOME folder
...This should result in the hg script being installed in $HOME/.local/bin/hg and the rest of the hg package in $HOME/.local/lib/pythonx.y/site-packages/.
Note, that the above is true for Python 2.6. There has been a bit of controversy among the Python core developers about what is the appropriate di...
How can I open a cmd window in a specific location?
...
Try out this "PowerToy" from Microsoft:
Open Command Window Here
This PowerToy adds an "Open Command
Window Here" context menu option on
file system folders, giving you a
quick way to open a command window
(cmd.exe) pointing at the selected
folder.
EDIT : T...