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Assignment in an if statement
I have a class Animal , and its subclass Dog .
I often find myself coding the following lines:
17 Answers
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How do I create a class instance from a string name in ruby?
I have the name of a class and I want to create an instance of that class so that I can loop through each rails attribute that is present in the schema of that class.
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Why use Dijkstra's Algorithm if Breadth First Search (BFS) can do the same thing faster?
...rce to every node in the traversed graph.
Meanwhile BFS basically just expands the search by one “step” (link, edge, whatever you want to call it in your application) on every iteration, which happens to have the effect of finding the smallest number of steps it takes to get to any given node f...
Showing line numbers in IPython/Jupyter Notebooks
...er keyboard shortcuts.
In more details CTRL - M (or ESC) bring you to command mode, then pressing the L keys should toggle the visibility of current cell line numbers. In more recent notebook versions Shift-L should toggle for all cells.
If you can't remember the shortcut, bring up the command pal...
How do I update all my CPAN modules to their latest versions?
...ve method to using upgrade from the default CPAN shell is to use cpanminus and cpan-outdated.
These are so easy and nimble to use that I hardly ever go back to CPAN shell. To upgrade all of your modules in one go, the command is:
cpan-outdated -p | cpanm
I recommend you install cpanminus like th...
Xcode debugger doesn't print objects and shows nil, when they aren't
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Ah ok, I created an empty project and can now see all the differences in the Build Settings, the deployment property Strip debug symbols during copy was set to YES.
– Binarian
Nov 11 '13 at 11:32
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What is a non-capturing group in regular expressions?
How are non-capturing groups, i.e. (?:) , used in regular expressions and what are they good for?
15 Answers
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Switching from zsh to bash on OSX, and back again?
So Im learning to develop in Rails, and have discovered the power of zsh. However, for some of my other tasks, I wish to use normal Bash. Although they are the same, I just feel comfortable with the lay out of bash in some situations. How do I switch back and forth, or turn zsh on and off? Thanks!
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String concatenation vs. string substitution in Python
In Python, the where and when of using string concatenation versus string substitution eludes me. As the string concatenation has seen large boosts in performance, is this (becoming more) a stylistic decision rather than a practical one?
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Disable orange outline highlight on focus
I am coding an app using jQuery, jqTouch and phonegap and have run across a persistent problem which arises when a user submits a form using the Go button on the soft keyboard.
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