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What is the difference between a pseudo-class and a pseudo-element in CSS?
... always consists of a "colon" (:) followed by the name of the pseudo-class and optionally by a value between parentheses.
Pseudo-classes are allowed in all sequences of simple selectors contained in a selector. Pseudo-classes are allowed anywhere in sequences of simple selectors, after the lead...
Parse a .py file, read the AST, modify it, then write back the modified source code
...on source code. Basically I want to read a .py file, generate the AST , and then write back the modified python source code (i.e. another .py file).
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Vertical (rotated) label in Android
I need 2 ways of showing vertical label in Android:
10 Answers
10
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Getting the last element of a list
...
some_list[-1] is the shortest and most Pythonic.
In fact, you can do much more with this syntax. The some_list[-n] syntax gets the nth-to-last element. So some_list[-1] gets the last element, some_list[-2] gets the second to last, etc, all the way down t...
Why is there a difference in checking null against a value in VB.NET and C#?
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VB.NET and C#.NET are different languages, built by different teams who have made different assumptions about usage; in this case the semantics of a NULL comparison.
My personal preference is for the VB.NET semantics, which in esse...
How to print the ld(linker) search path
...
You can do this by executing the following command:
ld --verbose | grep SEARCH_DIR | tr -s ' ;' \\012
gcc passes a few extra -L paths to the linker, which you can list with the following command:
gcc -print-search-dirs | sed '/^lib/b 1;d;:1;s,/[^/.][^/]*/\.\./,/,;t 1;...
Postgres - FATAL: database files are incompatible with server
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If you recently upgraded to 11 or 12 from 10.x you can run the below command to upgrade your postgres data directory retaining all data:
brew postgresql-upgrade-database
The above command is taken from the output of brew info postgres
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Where is Developer Command Prompt for VS2013?
I need to run web.exe file from my developer command prompt in Visual Studio 2013. By default, the command prompt is not installed in Visual Studio 2013.
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How to get .pem file from .key and .crt files?
...ust named with .crt or .key.
If the file's content begins with -----BEGIN and you can read it in a text editor:
The file uses base64, which is readable in ASCII, not binary format. The certificate is already in PEM format. Just change the extension to .pem.
If the file is in binary:
For the serv...
Why do we need C Unions?
...s are often used to convert between the binary representations of integers and floats:
union
{
int i;
float f;
} u;
// Convert floating-point bits to integer:
u.f = 3.14159f;
printf("As integer: %08x\n", u.i);
Although this is technically undefined behavior according to the C standard (you'r...