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Check if a given key already exists in a dictionary and increment it
...ct (available for Python 2.5+). This
from collections import defaultdict
my_dict = defaultdict(int)
my_dict[key] += 1
will do what you want.
For regular Python dicts, if there is no value for a given key, you will not get None when accessing the dict -- a KeyError will be raised. So if you want...
Alternatives to gprof [closed]
... **. When that is understood, you can see that -
gprof embodies certain myths about performance, such as:
that program counter sampling is useful.
It is only useful if you have an unnecessary hotspot bottleneck such as a bubble sort of a big array of scalar values. As soon as you, for example, ...
How do I set up a basic Ruby project?
... you can use the bundle gem command and rspec --init.
~/code $ bundle gem my_lib
create my_lib/Gemfile
create my_lib/Rakefile
create my_lib/LICENSE.txt
create my_lib/README.md
create my_lib/.gitignore
create my_lib/my_lib.gemspec
create my_lib/lib/my...
ES6 class variable alternatives
... true class variable you'd want to do something like the following:
class MyClass {}
MyClass.foo = 'bar';
From within a class method that variable can be accessed as this.constructor.foo (or MyClass.foo).
These class properties would not usually be accessible from to the class instance. i.e. My...
File name? Path name? Base name? Naming standard for pieces of a path
I keep getting myself in knots when I am manipulating paths and file names, because I don't have a common naming system that I use.
...
Why do I need to do `--set-upstream` all the time?
...g the syntax for git branch --set-upstream 1 is to do:
git push -u origin my_branch
... the first time that you push that branch. Or, to push to the current branch to a branch of the same name (handy for an alias):
git push -u origin HEAD
You only need to use -u once, and that sets up the asso...
String formatting named parameters?
...tring formatting method.
print('<a href="{0}">{0}</a>'.format(my_url))
which saves you from repeating the argument, or
print('<a href="{url}">{url}</a>'.format(url=my_url))
if you want named parameters.
print('<a href="{}">{}</a>'.format(my_url, my_url))
...
What exactly does Perl's “bless” do?
...
In general, bless associates an object with a class.
package MyClass;
my $object = { };
bless $object, "MyClass";
Now when you invoke a method on $object, Perl know which package to search for the method.
If the second argument is omitted, as in your example, the current package/cla...
Solving a “communications link failure” with JDBC and MySQL [duplicate]
I'm trying to connect to the local MySQL server but I keep getting an error.
25 Answers
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could not resolve host github.com error while cloning remote repository in git
...ote repository on Github and I am trying to clone the remote repository on my local machine. While cloning I am providing the clone URL & target folder.
...