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Check if a table exists in Rails
...ake task that won't work unless a table exists. I'm working with more than 20 engineers on a website so I want to make sure they have migrated the table before they can do a rake task which will populate that respective table.
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.NET HttpClient. How to POST string value?
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Todd Menier
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answered Mar 2 '13 at 16:22
Darin Dimitrov...
ImportError: No module named matplotlib.pyplot
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12 Answers
12
Active
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Merging dictionaries in C#
What's the best way to merge 2 or more dictionaries ( Dictionary<T1,T2> ) in C#?
(3.0 features like LINQ are fine).
2...
Get loop counter/index using for…of syntax in JavaScript
...both the value and the index to the function you give it:
var myArray = [123, 15, 187, 32];
myArray.forEach(function (value, i) {
console.log('%d: %s', i, value);
});
// Outputs:
// 0: 123
// 1: 15
// 2: 187
// 3: 32
Or ES6’s Array.prototype.entries, which now has support across current b...
How to get JSON from URL in JavaScript?
...() function:
$.getJSON('http://query.yahooapis.com/v1/public/yql?q=select%20%2a%20from%20yahoo.finance.quotes%20WHERE%20symbol%3D%27WRC%27&format=json&diagnostics=true&env=store://datatables.org/alltableswithkeys&callback', function(data) {
// JSON result in `data` variable
});
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How to use sed to replace only the first occurrence in a file?
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23 Answers
23
Active
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What does “mro()” do?
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214
Follow along...:
>>> class A(object): pass
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>>> A.__mro__
(<class '_...
How do I get the first n characters of a string without checking the size or going out of bounds?
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Stephen CStephen C
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How to install latest version of Node using Brew
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127
Have you run brew update first? If you don't do that, Homebrew can't update its formulas, and i...