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Check whether variable is number or string in JavaScript

...ject.prototype.toString; _.isString = function (obj) { return toString.call(obj) == '[object String]'; } This returns a boolean true for the following: _.isString("Jonathan"); // true _.isString(new String("Jonathan")); // true ...
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How to hide first section header in UITableView (grouped style)

... Actually, a better implementation (less likely to break in the future) is to use CGFLOAT_MIN instead of a hard-coded value. In other words, don't return 1.0f or 0.1f instead, return CGFLOAT_MIN If Apple ever changes the minimum a...
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Installing R with Homebrew

I'm trying to install R using Homebrew. I ran these commands which are recommended elsewhere on SO: 12 Answers ...
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How can I delete Docker's images?

... In order to delete all images, use the given command docker rmi $(docker images -q) In order to delete all containers, use the given command docker rm $(docker ps -a -q) Warning: This will destroy all your images and containers. It will n...
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How do you create different variable names while in a loop? [duplicate]

...can do this is with exec(). For example: for k in range(5): exec(f'cat_{k} = k*2') >>> print(cat_0) 0 >>> print(cat_1) 2 >>> print(cat_2) 4 >>> print(cat_3) 6 >>> print(cat_4) 8 Here I am taking advantage of the handy f string formatting in Pytho...
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What are 'closures' in .NET?

...thod and the variable j [CompilerGenerated] private sealed class <>c__DisplayClass2 { public <>c__DisplayClass2(); public void <fillFunc>b__0() { Console.Write("{0} ", this.j); } public int j; } for the function: static void fillFunc(int count) { ...
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C# pattern to prevent an event handler hooked twice [duplicate]

...ution and the best one (considering performance) is: private EventHandler _foo; public event EventHandler Foo { add { _foo -= value; _foo += value; } remove { _foo -= value; } } No Linq using required. No need to check for null before cancelling a subscrip...
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Ruby on Rails - Import Data from a CSV file

... The smarter_csv gem was specifically created for this use-case: to read data from CSV file and quickly create database entries. require 'smarter_csv' options = {} SmarterCSV.process('input_file.csv', options) do |chunk| chunk.each do |data_hash| ...
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Where to define custom error types in Ruby and/or Rails?

... error types in a Ruby library (gem) or Ruby on Rails application? Specifically: 5 Answers ...
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Razor-based view doesn't see referenced assemblies

...m another project in the same solution (with assembly name MyCoreDBLayer). All objects from MyCore.DBLayer worked perfectly in Controllers and Models but failed in Razor views with an error 'The type or namespace name 'DBLayer' does not exist in the namespace 'MyCore' (are you missing an assembly re...