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capturing self strongly in this block is likely to lead to a retain cycle
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Good answer, but I take small issue with you saying: “you can't refer to self or properties on self from within a block that will be strongly retained by self.” This is not strictly true. Please see my answer below. Better to say, “you must take...
Using the rJava package on Win7 64 bit with R
I'm trying to install rJava on a computer with Win 7 64 bit. When I run
12 Answers
1...
Is it possible to implement a Python for range loop without an iterator variable?
...hon?
– James McMahon
May 4 '09 at 5:20
1
@nemo Yes its just an acceptable variable name. In the i...
AngularJS: Basic example to use authentication in Single Page Application
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I've created a github repo summing up this article basically: https://medium.com/opinionated-angularjs/techniques-for-authentication-in-angularjs-applications-7bbf0346acec
ng-login Github repo
Plunker
I'll try to explain as good as possible, hope I help some of you out there:
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Retrieve only the queried element in an object array in MongoDB collection
...r to filter an array during projection, which has the benefit of including all matches, instead of just the first one.
db.test.aggregate([
// Get just the docs that contain a shapes element where color is 'red'
{$match: {'shapes.color': 'red'}},
{$project: {
shapes: {$filter: {
...
How to concatenate properties from multiple JavaScript objects
...n Javascript.
The Object.assign() method is used to copy the values of all enumerable own properties from one or more source objects to a target object. It will return the target object.
MDN documentation on Object.assign()
var o1 = { a: 1 };
var o2 = { b: 2 };
var o3 = { c: 3 };
var...
Generating Guids in Ruby
I have problem that is really easily solved with Guids.
10 Answers
10
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Using module 'subprocess' with timeout
...that contains command's merged stdout, stderr data.
check_output raises CalledProcessError on non-zero exit status as specified in the question's text unlike proc.communicate() method.
I've removed shell=True because it is often used unnecessarily. You can always add it back if cmd indeed requir...
Cron job every three days
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The answer is not correct because neither suggestion actually runs the job every 3 days. 0 0 */3 * * means run on the 1st, 4th, 7th, etc. (*/3 means 1-31/3 means 1,4,7...31) so the gap will be smaller at the end of the month. (It'll run 2 days in a row if the previous month had 3...
Timer function to provide time in nano seconds using C++
...psets, so you may want to make sure you do not have those chipset. Additionally some dual core AMDs may also cause a problem. See the second post by sebbbi, where he states:
QueryPerformanceCounter() and
QueryPerformanceFrequency() offer a
bit better resolution, but have
different issues. ...