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How to test if list element exists?
...es(foo) # TRUE
"b" %in% names(foo) # TRUE
"c" %in% names(foo) # FALSE
...and foo[["a"]] is safer than foo$a, since the latter uses partial matching and thus might also match a longer name:
x <- list(abc=4)
x$a # 4, since it partially matches abc
x[["a"]] # NULL, no match
[UPDATE] So, back t...
What do 'lazy' and 'greedy' mean in the context of regular expressions?
Could someone explain these two terms in an understandable way?
12 Answers
12
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What is the difference between And and AndAlso in VB.NET?
In VB.NET, what is the difference between And and AndAlso ? Which should I use?
11 Answers
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When is the thread pool used?
So I have an understanding of how Node.js works: it has a single listener thread that receives an event and then delegates it to a worker pool. The worker thread notifies the listener once it completes the work, and the listener then returns the response to the caller.
...
What is Cache-Control: private?
...r browser did have to suffer the delay of sending a request to the server, and wait for a response, but it did save having to re-download the static content.
Why Max-Age? Why Expires?
Because Last-Modified sucks.
Not everything on the server has a date associated with it. If I'm building a page o...
Why use pointers? [closed]
...tionality, missing data types or for pure perfomance. More below...
When and where should I use pointers?
Short answer here is: Where you cannot use anything else. In C you don't have any support for complex datatypes such as a string. There are also no way of passing a variable "by reference" ...
API to automatically upload apk to Google Play? [closed]
...t allows you to upload to any channel (ie. alpha, beta...) or update title and description and more.
From the docs:
Uploading new versions of an app Releasing apps, by assigning APKs to various Tracks (alpha, beta, staged rollout, or production)
Creating and modifying Google Play Store li...
Run command on the Ansible host
Is it possible to run commands on the Ansible host?
8 Answers
8
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How to use a variable for a key in a JavaScript object literal?
...ng are the same:
obj = { thetop : 10 };
obj = { "thetop" : 10 };
In ES5 and earlier, you cannot use a variable as a property name inside an object literal. Your only option is to do the following:
var thetop = "top";
// create the object literal
var aniArgs = {};
// Assign the variable proper...
How to pull remote branch from somebody else's repo
...ich somebody has forked. On their fork, they've created a new branch "foo" and made some changes. How do I pull their "foo" into a new branch also named "foo" in my repo?
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