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Python: most idiomatic way to convert None to empty string?
...
If you actually want your function to behave like the str() built-in, but return an empty string when the argument is None, do this:
def xstr(s):
if s is None:
return ''
return str(s)
...
Circle line-segment collision detection algorithm?
... exdx + eydy - dxh - dyk ) +
ex2 + ey2 -
2exh - 2eyk + h2 + k2 - r2 = 0
Finally,
t2( _d * _d ) + 2t( _e * _d - _d * _c ) + _e * _e - 2( _e*_c ) + _c * _c - r2 = 0
*Where _d is the vector d and * is the dot product.*
And then,
t2( _d * _d ) + 2t( _d * ( _e - _c ) ) + ( _e - _c ) * ( _e - _c ) - r2 = ...
Is bool a native C type?
... in the current C - C99, but not in C89/90.
In C99 the native type is actually called _Bool, while bool is a standard library macro defined in stdbool.h (which expectedly resolves to _Bool). Objects of type _Bool hold either 0 or 1, while true and false are also macros from stdbool.h.
Note, BTW, t...
Can you run GUI applications in a Docker container?
...
You can simply install a vncserver along with Firefox :)
I pushed an image, vnc/firefox, here: docker pull creack/firefox-vnc
The image has been made with this Dockerfile:
# Firefox over VNC
#
# VERSION 0.1
# DOCKER-VERSION ...
What does the C++ standard state the size of int, long type to be?
... value of the CHAR_BIT macro that defines the number of bits in a byte. In all but the most obscure platforms it's 8, and it can't be less than 8.
One additional constraint for char is that its size is always 1 byte, or CHAR_BIT bits (hence the name). This is stated explicitly in the standard.
The C...
How can I prevent SQL injection in PHP?
...is way it is impossible for an attacker to inject malicious SQL.
You basically have two options to achieve this:
Using PDO (for any supported database driver):
$stmt = $pdo->prepare('SELECT * FROM employees WHERE name = :name');
$stmt->execute([ 'name' => $name ]);
foreach ($stmt as $...
Max length UITextField
... that can be entered into a UITextField using swift? , I saw that if I use all 10 characters, I can't erase the character too.
...
print call stack in C or C++
Is there any way to dump the call stack in a running process in C or C++ every time a certain function is called? What I have in mind is something like this:
...
How to read if a checkbox is checked in PHP?
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this is the really good form to do this in pure simple php. but have to note that the value of a checkbox is string on when it is activated an a inexisting value if it is checked.
– Elvis Technologies
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How do I pass values to the constructor on my wcf service?
... How can I use it for self hosting? I receive an exception after calling to CreateServiceHost. I can only call to the protected method public override ServiceHostBase CreateServiceHost(string constructorString, Uri[] baseAddresses); The exception is The exception message was: 'ServiceHostF...