Yes, ensure ensures that the code is always evaluated. That’s why it’s called ensure. So, it is equivalent to Java’s and C#’s finally. The general flow of begin/rescue/else/ensure/end looks like this: begin # something which might raise an exception rescue SomeExceptionClass => some_variable # code that deals with some exception rescue SomeOtherException => some_other_variable # … Read more
For ruby >= 2.4 you can use sum: array.sum For ruby < 2.4 you can use inject: array.inject(0, :+) Note: the 0 base case is needed otherwise nil will be returned on empty arrays: > [].inject(:+) nil > [].inject(0, :+) 0
There’s a simple command built-in that will pull it: rvm implode This will remove the rvm/ directory and all the rubies built within it. In order to remove the final trace of rvm, you need to remove the rvm gem, too, if you installed that: gem uninstall rvm There may be elements left over from … Read more
Try adding –user-install instead of using sudo: gem install mygem –user-install
Just use Array#sample: [:foo, :bar].sample # => :foo, or :bar 🙂 It is available in Ruby 1.9.1+. To be also able to use it with an earlier version of Ruby, you could require “backports/1.9.1/array/sample”. Note that in Ruby 1.8.7 it exists under the unfortunate name choice; it was renamed in later version so you shouldn’t … Read more
In general, methods that end in ! indicate that the method will modify the object it’s called on. Ruby calls these as “dangerous methods” because they change state that someone else might have a reference to. Here’s a simple example for strings: foo = “A STRING” # a string called foo foo.downcase! # modifies foo … Read more
If you want to remove only leading and trailing whitespace (like PHP’s trim) you can use .strip, but if you want to remove all whitespace, you can use .gsub(/\s+/, “”) instead .
Using scan should do the trick: string.scan(/regex/)
Are you looking for the following? File.open(yourfile, ‘w’) { |file| file.write(“your text”) }
Rails has an except/except! method that returns the hash with those keys removed. If you’re already using Rails, there’s no sense in creating your own version of this. class Hash # Returns a hash that includes everything but the given keys. # hash = { a: true, b: false, c: nil} # hash.except(:c) # => … Read more