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Test if string is a number in Ruby on Rails
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is_number?( my_string )
# => true
Extend String Class.
If you want to be able to call is_number? directly on the string instead of passing it as a param to your helper function, then you need to define is_number? as an extension of the String class, like so:
class String
def is_number?
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How can I use Homebrew to install both Python 2 and 3 on Mac?
I need to be able to switch back and forth between Python 2 and 3. How do I do that using Homebrew as I don't want to mess with path and get into trouble.
Right now I have 2.7 installed through Homebrew.
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Upgrade python in a virtualenv
Is there a way to upgrade the version of python used in a virtualenv (e.g. if a bugfix release comes out)?
12 Answers
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Why would I use a templating engine? jsp include and jstl vs tiles, freemarker, velocity, sitemesh
I'm about to choose to way to organize my view (with spring-mvc, but that shouldn't matter much)
7 Answers
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How can I drop all the tables in a PostgreSQL database?
...MA public;
If you are using PostgreSQL 9.3 or greater, you may also need to restore the default grants.
GRANT ALL ON SCHEMA public TO postgres;
GRANT ALL ON SCHEMA public TO public;
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UITableViewCell with UITextView height in iOS 7?
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First of all, it is very important to note, that there is a big difference between UITextView and UILabel when it comes to how text is rendered. Not only does UITextView have insets on all borders, but also the text layout inside it is slightly different.
Ther...
Asynchronous vs Multithreading - Is there a difference?
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This question is darn near too general to answer.
In the general case, an asynchronous call does not necessarily create a new thread. That's one way to implement it, with a pre-existing thread pool or external process being other ways. It depends hea...
How to fully clean bin and obj folders within Visual Studio?
...Clean" menu item. I assumed this would clean (remove) the obj and bin directory.
However, as far as I can see, it does nothing.
Is there another way?
(please don't tell me to go to Windows Explorer or the cmd.exe)
I'd like to remove the obj and bin folder so that I can easily zip the whole thing.
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UITableView set to static cells. Is it possible to hide some of the cells programmatically?
UITableView set to static cells.
22 Answers
22
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Regular cast vs. static_cast vs. dynamic_cast [duplicate]
...rs, but there's one aspect of these languages that I've never really understood. I've obviously used regular casts i.e.
8 A...