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Why use def main()? [duplicate]
...ink I still have something else to add.
Reasons to have that if statement calling main() (in no particular order):
Other languages (like C and Java) have a main() function that is called when the program is executed. Using this if, we can make Python behave like them, which feels more familiar for ...
Migrating from JSF 1.2 to JSF 2.0
... JSP 2.x
If you're using JSP 2.x and want to keep using it, then you basically don't need to change anything else.
Gradually upgrading
If you're already using a suffix url-pattern for the FacesServlet, like *.jsf, then it's good to know that the FacesServlet will first scan for *.xhtml file and ...
Creating a dynamic choice field
...ted May 27 '16 at 18:04
Tim Tisdall
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answered Aug 6 '10 at 2:17
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How do I find the location of my Python site-packages directory?
...ib"])'
The per user site-packages directory (PEP 370) is where Python installs your local packages:
python -m site --user-site
If this points to a non-existing directory check the exit status of Python and see python -m site --help for explanations.
Hint: Running pip list --user or pip freeze -...
What is the difference between '/' and '//' when used for division?
...floating point division, and the latter is floor division, sometimes also called integer division.
In Python 2.2 or later in the 2.x line, there is no difference for integers unless you perform a from __future__ import division, which causes Python 2.x to adopt the 3.x behavior.
Regardless of the ...
Hash function that produces short hashes?
...m that's strong against intentional modification, I've found an algorithm called adler32 that produces pretty short (~8 character) results. Choose it from the dropdown here to try it out:
http://www.sha1-online.com/
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“Incorrect string value” when trying to insert UTF-8 into MySQL via JDBC?
...ter you can change the column encoding from utf8 to utf8mb4. This encoding allows storage of characters that occupy 4 bytes in UTF-8.
You may also have to set the server property character_set_server to utf8mb4 in the MySQL configuration file. It seems that Connector/J defaults to 3-byte Unicode ot...
Structure padding and packing
....
A note though - unaligned memory access is slower on architectures that allow it (like x86 and amd64), and is explicitly prohibited on strict alignment architectures like SPARC.
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What is “:-!!” in C code?
...sizeof(struct { int: -!!(e); }))
(e): Compute expression e.
!!(e): Logically negate twice: 0 if e == 0; otherwise 1.
-!!(e): Numerically negate the expression from step 2: 0 if it was 0; otherwise -1.
struct{int: -!!(0);} --> struct{int: 0;}: If it was zero, then we declare a struct with an an...
Google Chrome Extensions - Can't load local images with CSS
...ion that uses the content script feature to modify a website. More specifically, the background-image of said website.
8 ...