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How to update bower.json with installed packages?
In my project I've installed bower components without save option. Now, I would like update to bower.json ?
6 Answers
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How to use querySelectorAll only for elements that have a specific attribute set?
I'm trying to use document.querySelectorAll for all checkboxes that have the value attribute set.
3 Answers
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Fastest way to list all primes below N
...4.0 |
| sundaram3 | 416.0 |
+---------------------+-------+
Of all the methods tested, allowing numpy, for n=1000000,
primesfrom2to was the fastest tested.
+---------------------+-------+
| Method | ms |
+---------------------+-------+
| primesfrom2to | 15.9 |
| p...
'printf' vs. 'cout' in C++
...letely on operator overloading, so there is no issue with custom formats - all you do is define a subroutine taking std::ostream as the first argument and your type as second. As such, there are no namespace problems - as long you have a class (which isn't limited to one character), you can have wor...
Memory footprint of Haskell data types
... GHC creates a single instance of these constructors and shares it amongst all uses.
A word is 4 bytes on a 32-bit machine, and 8 bytes on a 64-bit machine.
So e.g.
data Uno = Uno a
data Due = Due a b
an Uno takes 2 words, and a Due takes 3.
The Int type is defined as
data Int = I# Int#
no...
Check for array not empty: any?
..." value in the array evaluates to true.
Similar methods to this are none?, all? and one?, where they all just check to see how many times true could be evaluated. which has nothing to do with the count of values found in a array.
case 1
>> a = []
=> []
>> a.any?
=> false
>> a...
Should the .gradle folder be added to version control?
Gradle creates a folder called .gradle . Should I track it with my version control (i.e. git)?
5 Answers
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How to get the host name of the current machine as defined in the Ansible hosts file?
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The necessary variable is inventory_hostname.
- name: Install this only for local dev machine
pip: name=pyramid
when: inventory_hostname == "local"
It is somewhat hidden in the documentation at the bottom of this section.
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Rails migrations: self.up and self.down versus change
... For example, in your case what is the reverse operation of add_column to call when you rollback? Of course it's remove_column. What is the inverse of create_table? It's drop_table. So in these cases rails know how to rollback and define a down method is superfluous (you can see in the documentation...
How well is Unicode supported in C++11?
...ization library
Input/output library
Regular expressions library
I think all but the first one provide terrible support. I'll get back to it in more detail after a quick detour through your other questions.
Does std::string do what it should?
Yes. According to the C++ standard, this is what ...