diff options
Diffstat (limited to 'ruby.html.markdown')
| -rw-r--r-- | ruby.html.markdown | 29 | 
1 files changed, 28 insertions, 1 deletions
| diff --git a/ruby.html.markdown b/ruby.html.markdown index f437adcf..4b96b71c 100644 --- a/ruby.html.markdown +++ b/ruby.html.markdown @@ -23,6 +23,15 @@ contributors:  ```ruby  # This is a comment +=begin +This is a multi-line comment. +The beginning line must start with "=begin" +and the ending line must start with "=end". + +You can do this, or start each line in +a multi-line comment with the # character. +=end +  # In Ruby, (almost) everything is an object.  # This includes numbers...  3.class #=> Integer @@ -172,6 +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 @@ -247,7 +259,7 @@ else    'else, also optional'  end -# If a condition controls invokation of a single statement rather than a block of code +# If a condition controls invocation of a single statement rather than a block of code  # you can use postfix-if notation  warnings = ['Patronimic is missing', 'Address too short']  puts("Some warnings occurred:\n" + warnings.join("\n"))  if !warnings.empty? @@ -315,6 +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' @@ -421,6 +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. | 
