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Better way to check if a Path is a File or a Directory?
... @KeyMs92 Its bitwise math. Basically, attr is some binary value with one bit meaning "this is a directory". The bitwise and & operator will return a binary value where only the bits that are on (1) in both the operands are turned on. In this case doing a bitwise and operation against att...
What does bundle exec rake mean?
...dler command to execute a script in the context of the current bundle (the one from your directory's Gemfile). rake db:migrate is the script where db is the namespace and migrate is the task name defined.
So bundle exec rake db:migrate executes the rake script with the command db:migrate in the con...
Lambda function in list comprehensions
...
The first one creates a single lambda function and calls it ten times.
The second one doesn't call the function. It creates 10 different lambda functions. It puts all of those in a list. To make it equivalent to the first you need:
[(l...
How should I validate an e-mail address?
...L_ADDRESS.matcher(target).matches();
}
}
Patterns viewable source
OR
One line solution from @AdamvandenHoven:
public final static boolean isValidEmail(CharSequence target) {
return !TextUtils.isEmpty(target) && android.util.Patterns.EMAIL_ADDRESS.matcher(target).matches();
}
...
How do I use .toLocaleTimeString() without displaying seconds?
... allowed options (it's based on a separate constructor but the options map one-to-one): developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/…
– Brian Peterson
Mar 11 at 18:42
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Using Java 8 to convert a list of objects into a string obtained from the toString() method
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One simple way is to append your list items in a StringBuilder
List<Integer> list = new ArrayList<>();
list.add(1);
list.add(2);
list.add(3);
StringBuilder b = new StringBuilder();
list.forEac...
Can't delete virtual device from Eclipse, android
...tory.
In .android there should be a avd folder
In the avd folder should be one or multiple .ini file and a corresponding *.avd virtual device folder.
Delete both the .ini file and the .avd folder you want to get rid of.
Return to the Android sdk and AVD manager.
I hope this helps...
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Parsing a comma-delimited std::string [duplicate]
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Input one number at a time, and check whether the following character is ,. If so, discard it.
#include <vector>
#include <string>
#include <sstream>
#include <iostream>
int main()
{
std::string str =...
How to use the 'main' parameter in package.json?
I have done quite some search already. However, still having doubts about the 'main' parameter in the package.json of a Node project.
...
Declaring an enum within a class
...al (or at least outside Car).
It makes no difference. If there is a global one then the local one is still used anyway as it is closer to the current scope. Note that if you define those function outside of the class definition then you'll need to explicitly specify Car::Color in the function's inte...