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What is the difference between “def” and “val” to define a function

...ng var as I need to change it to 3 later val sq = x*x // evaluates right now x = 3 // no effect! sq is already evaluated println(sq) Surprisingly, this will print 4 and not 9! val (even var) is evaluated immediately and assigned. Now change val to def.. it will print 9! Def is a function cal...
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Hosting ASP.NET in IIS7 gives Access is denied?

... for me when I enabled windows authentication in IIS , working fine now. thanks – Singaravelan Jan 19 '18 at 11:15 add a comment  |  ...
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Convert between UIImage and Base64 string

Does anyone know how to convert a UIImage to a Base64 string, and then reverse it? 24 Answers ...
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Should I call Close() or Dispose() for stream objects?

...of these classes. They've also defined a public method called Close() . Now that confuses me, as to what should I call once I'm done with objects? What if I call both? ...
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How do I unbind “hover” in jQuery?

...ing you to expressly remove each of the literal event names. Using $.off() now allows you to drop both mouse events using the same shorthand. Edit 2016: Still a popular question so it's worth drawing attention to @Dennis98's point in the comments below that in jQuery 1.9+, the "hover" event was de...
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Is it good style to explicitly return in Ruby?

...... def plus_one_to_y(x) @y = x + 1 puts "In plus_one_to_y" end Now the function is broken if anything expects a returned value. If nothing expects a returned value, it's fine. Clearly if somewhere further down the code chain, something calling this is expecting a returned value, it's g...
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How to work with Git branches and Rails migrations

... @pisaruk I know you answered this six years ago, but reading I'm curious what an example of a non-reversible migration would be. I'm having a hard time imagining a situation. I guess the simplest would be a dropped column containing a ...
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ActiveRecord OR query

...s noted in this pull request https://github.com/rails/rails/pull/9052 For now, simply sticking with the following works great: Foo.where('foo= ? OR bar= ?', 'bar', 'bar') Update: According to https://github.com/rails/rails/pull/16052 the or feature will be available in Rails 5 Update: Feature h...
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ImportError: No module named pip

... I am having python2 and 3 on the same machine but for now I wanted to use Python3. Hence I had to modify the comment above to sudo python3 -m pip install matplotlib (I had to do this via sudo, otherwise some folder permission didnt work). (edited the answer correspondingly) ...
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Devise - How do I forbid certain users from signing in?

...d self.is_active? end end UPDATE As Matt Huggins notes, the method is now called active_for_authentication? (Documentation) share | improve this answer | follow ...