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Difference between Python's Generators and Iterators
What is the difference between iterators and generators? Some examples for when you would use each case would be helpful.
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twig: IF with multiple conditions
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If I recall correctly Twig doesn't support || and && operators, but requires or and and to be used respectively. I'd also use parentheses to denote the two statements more clearly although this isn't technically a requirement.
{%if ( fields | length > 0 ) or ...
Python exit commands - why so many and when should each be used?
It seems that python supports many different commands to stop script execution. The choices I've found are: quit() , exit() , sys.exit() , os._exit()
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What is Type-safe?
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Type safety means that the compiler will validate types while compiling, and throw an error if you try to assign the wrong type to a variable.
Some simple examples:
// Fails, Trying to put an integer in a string
String one = 1;
// Also fails.
int foo = "bar";
This also applies to method argume...
Check synchronously if file/directory exists in Node.js
...version of lstat, etc.
lstatSync tells you both whether something exists, and if so, whether it's a file or a directory (or in some file systems, a symbolic link, block device, character device, etc.), e.g. if you need to know if it exists and is a directory:
var fs = require('fs');
try {
// Q...
What values should I use for CFBundleVersion and CFBundleShortVersionString?
This is my first iOS app submission and I don't want my app rejected.
7 Answers
7
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Retrieving Android API version programmatically
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As described in the Android documentation, the SDK level (integer) the phone is running is available in:
android.os.Build.VERSION.SDK_INT
The class corresponding to this int is in the android.os.Build.VERSION_CODES class.
Code example:
if (a...
What does “var FOO = FOO || {}” (assign a variable or an empty object to that variable) mean in Java
...s is used to create a namespace, i.e. a named object under which functions and variables can be created without unduly polluting the global object.
The reason why it's used is so that if you have two (or more) files:
var MY_NAMESPACE = MY_NAMESPACE || {};
MY_NAMESPACE.func1 = {
}
and
var MY_NAM...
Signed to unsigned conversion in C - is it always safe?
...unsigned values, resulting in a large result (depending on the values of u and i).
Long Answer
According to the C99 Standard:
6.3.1.8 Usual arithmetic conversions
If both operands have the same type, then no further conversion is needed.
Otherwise, if both operands have signed intege...
How to decide font color in white or black depending on background color?
...need to break the hex code into 3 pieces to get the individual red, green, and blue intensities. Each 2 digits of the code represent a value in hexadecimal (base-16) notation. I won't get into the details of the conversion here, they're easy to look up.
Once you have the intensities for the individ...