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What is causing this ActiveRecord::ReadOnlyRecord error?
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Rails 2.3.3 and lower
From the ActiveRecord CHANGELOG(v1.12.0, October 16th, 2005):
Introduce read-only records. If you call object.readonly! then it will
mark the object as read-only and raise
ReadOnlyRecord if you call
obje...
NSString tokenize in Objective-C
...red Nov 3 '08 at 21:10
Adam AlexanderAdam Alexander
14.9k55 gold badges3838 silver badges4141 bronze badges
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Tab key == 4 spaces and auto-indent after curly braces in Vim
...use tabs (converting spaces to tabs, bad!), makes the tab key == 4 spaces, and automatically indent code after curly brace blocks like Emacs does?
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jQuery get textarea text
Recently I have started playing with jQuery, and have been following a couple of tutorials. Now I feel slightly competent with using it (it's pretty easy), and I thought it would be cool if I were able to make a 'console' on my webpage (as in, you press the ` key like you do in FPS games, etc.), a...
How can I sort generic list DESC and ASC?
How can I sort generic list DESC and ASC? With LINQ and without LINQ? I'm using VS2008.
5 Answers
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Can I assume (bool)true == (int)1 for any C++ compiler?
...are redundant. In your expression:
true == 1
Integral promotion applies and the bool value will be promoted to an int and this promotion must yield 1.
Reference: 4.7 [conv.integral] / 4: If the source type is bool... true is converted to one.
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What is the difference between string primitives and String objects in JavaScript?
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JavaScript has two main type categories, primivites and objects.
var s = 'test';
var ss = new String('test');
The single quote/double quote patterns are identical in terms of functionality. That aside, the behaviour you are trying to name is called auto-boxing. So what actu...
Flatten an irregular list of lists
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Using generator functions can make your example a little easier to read and probably boost the performance.
Python 2
def flatten(l):
for el in l:
if isinstance(el, collections.Iterable) and not isinstance(el, basestring):
for sub in flatten(el):
yield sub...
How do I conditionally apply CSS styles in AngularJS?
...ange dynamically. Think programmable control of the style values.
ng-show and ng-hide - use if you only need to show or hide something (modifies CSS)
ng-if - new in version 1.1.5, use instead of the more verbose ng-switch if you only need to check for a single condition (modifies DOM)
ng-switch - u...
Where does R store packages?
...all.packages() function in R is the automatic unzipping utility that gets and install packages in R.
4 Answers
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