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Pass props to parent component in React.js
Is there not a simple way to pass a child's props to its parent using events, in React.js?
7 Answers
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The performance impact of using instanceof in Java
I am working on an application and one design approach involves extremely heavy use of the instanceof operator. While I know that OO design generally tries to avoid using instanceof , that is a different story and this question is purely related to performance. I was wondering if there is any per...
Summarizing multiple columns with dplyr? [duplicate]
I'm struggling a bit with the dplyr-syntax. I have a data frame with different variables and one grouping variable. Now I want to calculate the mean for each column within each group, using dplyr in R.
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ElasticSearch: Unassigned Shards, how to fix?
I have an ES cluster with 4 nodes:
24 Answers
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Best way to give a variable a default value (simulate Perl ||, ||= )
I love doing this sort of thing in Perl: $foo = $bar || $baz to assign $baz to $foo if $bar is empty or undefined. You also have $foo ||= $bletch which will only assign $bletch to $foo if $foo is not defined or empty.
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One line if-condition-assignment
I have the following code
14 Answers
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RedirectToAction with parameter
I have an action I call from an anchor thusly, Site/Controller/Action/ID where ID is an int .
14 Answers
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Git commits are duplicated in the same branch after doing a rebase
I understand the scenario presented in Pro Git about The Perils of Rebasing . The author basically tells you how to avoid duplicated commits:
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How do I change the language of moment.js?
I am trying to change the language of the date which is being set by moment.js. The default one is English, but I want to set the German language. These is what I tried:
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How to make exe files from a node.js app?
I have a node app that I wrote, that I run as follows:
16 Answers
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