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If my interface must return Task what is the best way to have a no-operation implementation?
...g Task.CompletedTask to accomplish this.
Pre .net 4.6:
Using Task.FromResult(0) or Task.FromResult<object>(null) will incur less overhead than creating a Task with a no-op expression. When creating a Task with a result pre-determined, there is no scheduling overhead involved.
...
Android: I am unable to have ViewPager WRAP_CONTENT
...eSpec, int heightMeasureSpec) {
int height = 0;
for(int i = 0; i < getChildCount(); i++) {
View child = getChildAt(i);
child.measure(widthMeasureSpec, MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
int h = child.getMeasuredHeight();
if(h > he...
A migration to add unique constraint to a combination of columns
... you want to use for the constraint.
class AddUniqeConstraintToShipments < ActiveRecord::Migration
def up
execute <<-SQL
alter table shipments
add constraint shipment_tracking_number unique (tracking_number, carrier);
SQL
end
def down
execute <<-SQL
...
“git diff” does nothing
...
The default output for git diff is the list of changes which have not been committed / added to the index. If there are no changes, then there is no output.
git diff [--options] [--] […]
This form is to view the changes you...
Should all Python classes extend object?
...yle class, which, amongst other effects, causes type to give different results:
>>> class Foo: pass
...
>>> type(Foo())
<type 'instance'>
vs.
>>> class Bar(object): pass
...
>>> type(Bar())
<class '__main__.Bar'>
Also the rules for multiple inh...
How to generate all permutations of a list?
...t(itertools.permutations([1, 2, 3]))
If you're using an older Python (<2.6) for some reason or are just curious to know how it works, here's one nice approach, taken from http://code.activestate.com/recipes/252178/:
def all_perms(elements):
if len(elements) <=1:
yield element...
How to download source in ZIP format from GitHub?
... Code tab:
If you don't see the button:
Make sure you've selected <> Code tab from right side navigation menu, or
Repo may not have a zip prepared. Add /archive/master.zip to the end of the repository URL and to generate a zipfile of the master branch:
http://github.com/user/reposito...
Node.js app can't run on port 80 even though there's no other process blocking the port
...create a reverse proxy on a vhost. If your node is running on port 8080:
<VirtualHost 127.0.0.1:80>
ServerName myLocalServer
ProxyPass / http://localhost:8080/
ProxyPassReverse / http://localhost:8080/
</VirtualHost>
Of course, add server to /etc/host...
How to read/write a boolean when implementing the Parcelable interface?
...om object. I start writing a myObjectList class which extends ArrayList<myObject> and implement Parcelable .
12 ...
Run a single test method with maven
...so work; both in the method name and class name.
If you're testing in a multi-module project, specify the module that the test is in with -pl <module-name>.
For integration tests use it.test=... option instead of test=...:
mvn -pl <module-name> -Dit.test=TestCircle#xyz integration-tes...