diff options
Diffstat (limited to 'ruby.html.markdown')
| -rw-r--r-- | ruby.html.markdown | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/ruby.html.markdown b/ruby.html.markdown index 376f4a47..8e5f924a 100644 --- a/ruby.html.markdown +++ b/ruby.html.markdown @@ -181,6 +181,9 @@ array = [1, 2, 3, 4, 5] #=> [1, 2, 3, 4, 5] # Arrays can contain different types of items. [1, 'hello', false] #=> [1, "hello", false] +# You might prefer %w instead of quotes +%w[foo bar baz] #=> ["foo", "bar", "baz"] + # Arrays can be indexed. # From the front... array[0] #=> 1 @@ -324,6 +327,11 @@ puts doubled puts array #=> [1,2,3,4,5] +# another useful syntax is .map(&:method) +a = ["FOO", "BAR", "BAZ"] +a.map { |s| s.downcase } #=> ["foo", "bar", "baz"] +a.map(&:downcase) #=> ["foo", "bar", "baz"] + # Case construct grade = 'B' @@ -430,6 +438,16 @@ def guests(*array) array.each { |guest| puts guest } end +# There is also the shorthand block syntax. It's most useful when you need +# to call a simple method on all array items. +upcased = ['Watch', 'these', 'words', 'get', 'upcased'].map(&:upcase) +puts upcased +#=> ["WATCH", "THESE", "WORDS", "GET", "UPCASED"] + +sum = [1, 2, 3, 4, 5].reduce(&:+) +puts sum +#=> 15 + # Destructuring # Ruby will automatically destructure arrays on assignment to multiple variables. @@ -652,4 +670,4 @@ Something.new.qux #=> "qux" - [Ruby from other languages](https://www.ruby-lang.org/en/documentation/ruby-from-other-languages/) - [Programming Ruby](http://www.amazon.com/Programming-Ruby-1-9-2-0-Programmers/dp/1937785491/) - An older [free edition](http://ruby-doc.com/docs/ProgrammingRuby/) is available online. - [Ruby Style Guide](https://github.com/bbatsov/ruby-style-guide) - A community-driven Ruby coding style guide. -- [Try Ruby](http://tryruby.org) - Learn the basic of Ruby programming language, interactive in the browser. +- [Try Ruby](https://try.ruby-lang.org/) - Learn the basic of Ruby programming language, interactive in the browser. |