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if/else in a list comprehension
...ts from the source iterable.
Conditional expressions can be used in all kinds of situations where you want to choose between two expression values based on some condition. This does the same as the ternary operator ?: that exists in other languages. For example:
value = 123
print(value, 'is', 'e...
How do I update pip itself from inside my virtual environment?
I'm able to update pip-managed packages, but how do I update pip itself? According to pip --version , I currently have pip 1.1 installed in my virtualenv and I want to update to the latest version.
...
html select option separator
How do you make a separator in a select tag?
14 Answers
14
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How can I give eclipse more memory than 512M?
... a lot of problems trying to get Eclipse to accept as much memory as I'd like it to be able to use (between 2 and 4 gigs for example).
Open eclipse.ini in the Eclipse installation directory.
You should be able to change the memory sizes after -vmargs up to 1024 without a problem up to some maximum ...
Fastest way to duplicate an array in JavaScript - slice vs. 'for' loop
...STEST)
map A.map(function(e){return e;});
There has been a huuuge BENCHMARKS thread, providing following information:
for blink browsers slice() is the fastest method, concat() is a bit slower, and while loop is 2.4x slower.
for other browsers while loop is the fastest method, since those browser...
a href link for entire div in HTML/CSS
... </div>
</a>
which is semantically incorrect, but it will work.
<div style="cursor: pointer;" onclick="window.location='http://google.com';">
Hello world
</div>
which is semantically correct but it involves using JS.
<a href="http://google.com">
<span s...
How to remove trailing whitespace of all files recursively?
...Ignores .git and .svn folders and their contents. Also it won't leave a backup file.
export LC_CTYPE=C
export LANG=C
find . -not \( -name .svn -prune -o -name .git -prune \) -type f -print0 | xargs -0 sed -i '' -E "s/[[:space:]]*$//"
...
Git/GitHub can't push to master
...erences between the transfer protocols used by Git are explained in the link below.)
If you want to change the URL of origin, you can just do:
git remote set-url origin git@github.com:my_user_name/my_repo.git
or
git remote set-url origin https://github.com/my_user_name/my_repo.git
More inform...
Good examples of Not a Functor/Functor/Applicative/Monad?
...tructor which is not a Functor:
newtype T a = T (a -> Int)
You can make a contravariant functor out of it, but not a (covariant) functor. Try writing fmap and you'll fail. Note that the contravariant functor version is reversed:
fmap :: Functor f => (a -> b) -> f a ->...
What is the C# equivalent of NaN or IsNumeric?
...characters within the string are digits, then another approach should be taken.
example 1:
public Boolean IsNumber(String s) {
Boolean value = true;
foreach(Char c in s.ToCharArray()) {
value = value && Char.IsDigit(c);
}
return value;
}
or if you want to be a little more ...