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Why is `[` better than `subset`?

...vars, drop = drop]. The problem is how to get from the unquoted subset and select arguments to something that you can validly pass to [.data.frame. – joran Oct 2 '17 at 21:33 ...
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Pass props to parent component in React.js

...list of services (with names and prices) and it will calculate a total the selected prices. Children are blissfully ignorant ServiceItem is the child-component in this example. It doesn’t have many opinions about the outside world. It requires a few props, one of which is a function to be called...
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The definitive guide to form-based website authentication [closed]

... A cryptographic hash should not be used for password storage because user-selected passwords are not strong enough (i.e. do not usually contain enough entropy) and a password guessing attack could be completed in a relatively short time by an attacker with access to the hashes. This is why KDFs are...
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Twig ternary operator, Shorthand if-then-else

... {{ (ability.id in company_abilities) ? 'selected' : '' }} The ternary operator is documented under 'other operators' share | improve this answer | ...
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How can I change the copyright template in Xcode 4?

... Xcode 4 (and above) stores this on a per-project basis. If you select the project in the Project Navigator (Cmd-1) and open the File Inspector (Cmd-Opt-1), you'll see a field for "Organization" under "Project Document". ...
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Which HTTP methods match up to which CRUD methods?

...est HTTP verbs are GET, POST, PATCH, PUT and DELETE Overview HTTP GET - SELECT/Request HTTP PUT - UPDATE HTTP POST - INSERT/Create HTTP PATCH - When PUTting a complete resource representation is cumbersome and utilizes more bandwidth, e.g.: when you have to update partially a column HTTP DELETE ...
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presentViewController:animated:YES view will not appear until user taps again

...ese sources. I've found the issue by using a UITableViewCell which had its selectionStyle set to UITableViewCellSelectionStyleNone, so that no selection animation triggered the runloop after the row selection handler ran. To fix it (until Apple does something) you can trigger the main runloop by s...
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Duplicate AssemblyVersion Attribute

....cs can now be set on the project itself. Open the project properties and select the Package tab to see the new settings. The Eric L. Anderson's post "Duplicate ‘System.Reflection.AssemblyCompanyAttribute’ attribute" describes 3 options : remove the conflicting items from the AssemblyIn...
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MySQL - length() vs char_length()

... in two bytes. Or UTF-8, where the number of bytes varies. For example: select length(_utf8 '€'), char_length(_utf8 '€') --> 3, 1 As you can see the Euro sign occupies 3 bytes (it's encoded as 0xE282AC in UTF-8) even though it's only one character. ...
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Prevent a webpage from navigating away using JavaScript

... or not the user gets the Confirm Navigation prompt. With the text in the selected answer you see redundant prompts: share | improve this answer | follow | ...