Fix grammar errors, typos, and improve readability of array.rb

array.rb

@@ -3,20 +3,20 @@ class Array
   #   shuffle!(random: Random) -> self
   #
   # Shuffles all elements in +self+ into a random order,
-  # as selected by the object given by keyword argument +random+;
-  # returns +self+:
+  # as selected by the object given by the keyword argument +random+.
+  # Returns +self+:
   #
   #   a =             [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
   #   a.shuffle! # => [5, 3, 8, 7, 6, 1, 9, 4, 2, 0]
   #   a.shuffle! # => [9, 4, 0, 6, 2, 8, 1, 5, 3, 7]
   #
-  #   Duplicate elements are included:
+  #  Duplicate elements are included:
   #
   #   a =             [0, 1, 0, 1, 0, 1, 0, 1, 0, 1]
   #   a.shuffle! # => [1, 0, 0, 1, 1, 0, 1, 0, 0, 1]
   #   a.shuffle! # => [0, 1, 0, 1, 1, 0, 1, 0, 1, 0]
   #
-  # The object given with keyword argument +random+ is used as the random number generator.
+  # The object given with the keyword argument +random+ is used as the random number generator.
   #
   # Related: see {Methods for Assigning}[rdoc-ref:Array@Methods+for+Assigning].
   def shuffle!(random: Random)
@@ -27,7 +27,7 @@ def shuffle!(random: Random)
   #   shuffle(random: Random) -> new_array
   #
   # Returns a new array containing all elements from +self+ in a random order,
-  # as selected by the object given by keyword argument +random+:
+  # as selected by the object given by the keyword argument +random+:
   #
   #   a =            [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
   #   a.shuffle # => [0, 8, 1, 9, 6, 3, 4, 7, 2, 5]
@@ -39,7 +39,7 @@ def shuffle!(random: Random)
   #   a.shuffle # => [1, 0, 1, 1, 0, 0, 1, 0, 0, 1]
   #   a.shuffle # => [1, 1, 0, 0, 0, 1, 1, 0, 0, 1]
   #
-  # The object given with keyword argument +random+ is used as the random number generator.
+  # The object given with the keyword argument +random+ is used as the random number generator.
   #
   # Related: see {Methods for Fetching}[rdoc-ref:Array@Methods+for+Fetching].
   def shuffle(random: Random)
@@ -51,24 +51,23 @@ def shuffle(random: Random)
   #   sample(count, random: Random) -> new_ary
   #
   # Returns random elements from +self+,
-  # as selected by the object given by keyword argument +random+.
+  # as selected by the object given by the keyword argument +random+.
   #
   # With no argument +count+ given, returns one random element from +self+:
   #
-  #    a = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
-  #    a.sample # => 3
-  #    a.sample # => 8
+  #   a = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
+  #   a.sample # => 3
+  #   a.sample # => 8
   #
   # Returns +nil+ if +self+ is empty:
   #
-  #    [].sample # => nil
+  #   [].sample # => nil
   #
-  #
-  # With non-negative numeric argument +count+ given,
+  # With a non-negative numeric argument +count+ given,
   # returns a new array containing +count+ random elements from +self+:
   #
-  #    a.sample(3) # => [8, 9, 2]
-  #    a.sample(6) # => [9, 6, 0, 3, 1, 4]
+  #   a.sample(3) # => [8, 9, 2]
+  #   a.sample(6) # => [9, 6, 0, 3, 1, 4]
   #
   # The order of the result array is unrelated to the order of +self+.
   #
@@ -78,19 +77,19 @@ def shuffle(random: Random)
   #
   # May return duplicates in +self+:
   #
-  #    a = [1, 1, 1, 2, 2, 3]
-  #    a.sample(a.size) # => [1, 1, 3, 2, 1, 2]
+  #   a = [1, 1, 1, 2, 2, 3]
+  #   a.sample(a.size) # => [1, 1, 3, 2, 1, 2]
   #
   # Returns no more than <tt>a.size</tt> elements
   # (because no new duplicates are introduced):
   #
-  #    a.sample(50) # => [6, 4, 1, 8, 5, 9, 0, 2, 3, 7]
+  #   a.sample(50) # => [6, 4, 1, 8, 5, 9, 0, 2, 3, 7]
   #
-  # The object given with keyword argument +random+ is used as the random number generator:
+  # The object given with the keyword argument +random+ is used as the random number generator:
   #
-  #    a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
-  #    a.sample(random: Random.new(1))     #=> 6
-  #    a.sample(4, random: Random.new(1))  #=> [6, 10, 9, 2]
+  #   a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+  #   a.sample(random: Random.new(1))     # => 6
+  #   a.sample(4, random: Random.new(1))  # => [6, 10, 9, 2]
   #
   # Related: see {Methods for Fetching}[rdoc-ref:Array@Methods+for+Fetching].
   def sample(n = (ary = false), random: Random)
@@ -119,7 +118,7 @@ def sample(n = (ary = false), random: Random)
   #
   #   [].first # => nil
   #
-  # With non-negative integer argument +count+ given,
+  # With a non-negative integer argument +count+ given,
   # returns the first +count+ elements (as available) in a new array:
   #
   #   a.first(0)  # => []
@@ -141,8 +140,8 @@ def first n = unspecified = true
   end
 
   # call-seq:
-  #  last  -> last_object or nil
-  #  last(n) -> new_array
+  #   last  -> last_object or nil
+  #   last(n) -> new_array
   #
   # Returns elements from +self+, or +nil+; +self+ is not modified.
   #
@@ -153,8 +152,7 @@ def first n = unspecified = true
   #   a # => [:foo, "bar", 2]
   #   [].last # => nil
   #
-  #
-  # With non-negative integer argument +n+ is given,
+  # With a non-negative integer argument +n+ given,
   # returns a new array containing the trailing +n+ elements of +self+, as available:
   #
   #   a = [:foo, 'bar', 2]
@@ -177,38 +175,37 @@ def last n = unspecified = true
     end
   end
 
-  #  call-seq:
-  #    fetch_values(*indexes) -> new_array
-  #    fetch_values(*indexes) {|index| ... } -> new_array
+  # call-seq:
+  #   fetch_values(*indexes) -> new_array
+  #   fetch_values(*indexes) {|index| ... } -> new_array
   #
-  #  With no block given, returns a new array containing the elements of +self+
-  #  at the offsets given by +indexes+;
-  #  each of the +indexes+ must be an
-  #  {integer-convertible object}[rdoc-ref:implicit_conversion.rdoc@Integer-Convertible+Objects]:
+  # With no block given, returns a new array containing the elements of +self+
+  # at the offsets specified by +indexes+. Each of the +indexes+ must be an
+  # {integer-convertible object}[rdoc-ref:implicit_conversion.rdoc@Integer-Convertible+Objects]:
   #
   #    a = [:foo, :bar, :baz]
   #    a.fetch_values(3, 1)   # => [:baz, :foo]
   #    a.fetch_values(3.1, 1) # => [:baz, :foo]
   #    a.fetch_values         # => []
   #
-  #  For a negative index, counts backwards from the end of the array:
+  # For a negative index, counts backwards from the end of the array:
   #
   #    a.fetch_values([-2, -1]) # [:bar, :baz]
   #
-  #  When no block is given, raises an exception if any index is out of range.
+  # When no block is given, raises an exception if any index is out of range.
   #
-  #  With a block given, for each index:
+  # With a block given, for each index:
   #
-  #  - If the index in in range, uses an element of +self+ (as above).
-  #  - Otherwise calls, the block with the index, and uses the block's return value.
+  # - If the index is in range, uses an element of +self+ (as above).
+  # - Otherwise, calls the block with the index and uses the block's return value.
   #
-  #  Example:
+  # Example:
   #
-  #    a = [:foo, :bar, :baz]
-  #    a.fetch_values(1, 0, 42, 777) {|index| index.to_s}
-  #    # => [:bar, :foo, "42", "777"]
+  #   a = [:foo, :bar, :baz]
+  #   a.fetch_values(1, 0, 42, 777) {|index| index.to_s }
+  #   # => [:bar, :foo, "42", "777"]
   #
-  #  Related: see {Methods for Fetching}[rdoc-ref:Array@Methods+for+Fetching].
+  # Related: see {Methods for Fetching}[rdoc-ref:Array@Methods+for+Fetching].
   def fetch_values(*indexes, &block)
     indexes.map! { |i| fetch(i, &block) }
     indexes