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Exporting a function in shell
...n parent shell (bash, sh or ksh) so that the function will be available to all the child process launced from the parent process?
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How to organize large R programs?
...l as a means for namespaces.
Just running source() over code works for really short snippets. Everything else should be in a package -- even if you do not plan to publish it as you can write internal packages for internal repositories.
As for the 'how to edit' part, the R Internals manual has ex...
Where in memory are my variables stored in C?
...declared in functions), variables (in main function), pointers, and dynamically allocated space (using malloc and calloc) get stored in memory?
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How to get first character of string?
...le what you say is true, unfortunately charAt() without any parameters actually runs about 10x slower than chartAt(0) in Firefox as of Firefox 71. See for yourself here: jsperf.com/testing-the-first-character-in-a-string/1
– Stephen M Irving
Dec 16 '19 at 21:54...
How do I set up DNS for an apex domain (no www) pointing to a Heroku app?
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(Note: root, base, apex domains are all the same thing. Using interchangeably for google-foo.)
Traditionally, to point your apex domain you'd use an A record pointing to your server's IP. This solution doesn't scale and isn't viable for a cloud platform like H...
Formatting floats without trailing zeros
...ptimization is bad, but it's because the OP's trick requires you to remove all zeroes THEN all decimals and then NOT MORE ZEROS. Gabriel's approach just removes all zeros and periods until it hits something else.
– Scott Stafford
May 11 at 14:47
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When should TaskCompletionSource be used?
AFAIK, all it knows is that at some point, its SetResult or SetException method is being called to complete the Task<T> exposed through its Task property.
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What does @@variable mean in Ruby?
...the classes; setting the value in an instance of one changes the value for all other instances of that class and even child classes, where a variable named @shared, with one @, would not be.
[Update]
As Phrogz mentions in the comments, it's a common idiom in Ruby to track class-level data with an ...
How to enumerate an enum with String type?
...h Xcode 10), just add protocol conformance to CaseIterable to benefit from allCases. To add this protocol conformance, you simply need to write somewhere:
extension Suit: CaseIterable {}
If the enum is your own, you may specify the conformance directly in the declaration:
enum Suit: String, CaseIte...
Finding the number of days between two dates
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What about leap seconds? Not all days have exactly 24*60*60 seconds. This code might be sufficient for practical purposes but it's not exact in sone extremely rare edge cases.
– Benjamin Brizzi
Aug 1 '12 at 8:15
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