[DOC] Fix hash style for Array#flatten

Author: peterzhu2118

array.c

@@ -6803,17 +6803,17 @@ rb_ary_flatten_bang(int argc, VALUE *argv, VALUE ary)
  *  With non-negative integer argument +depth+, flattens recursively through +depth+ levels:
  *
  *    a = [ 0, [ 1, [2, 3], 4 ], 5, {foo: 0}, Set.new([6, 7]) ]
- *    a              # => [0, [1, [2, 3], 4], 5, {:foo=>0}, #<Set: {6, 7}>]
- *    a.flatten(0)   # => [0, [1, [2, 3], 4], 5, {:foo=>0}, #<Set: {6, 7}>]
- *    a.flatten(1  ) # => [0, 1, [2, 3], 4, 5, {:foo=>0}, #<Set: {6, 7}>]
- *    a.flatten(1.1) # => [0, 1, [2, 3], 4, 5, {:foo=>0}, #<Set: {6, 7}>]
- *    a.flatten(2)   # => [0, 1, 2, 3, 4, 5, {:foo=>0}, #<Set: {6, 7}>]
- *    a.flatten(3)   # => [0, 1, 2, 3, 4, 5, {:foo=>0}, #<Set: {6, 7}>]
+ *    a              # => [0, [1, [2, 3], 4], 5, {foo: 0}, #<Set: {6, 7}>]
+ *    a.flatten(0)   # => [0, [1, [2, 3], 4], 5, {foo: 0}, #<Set: {6, 7}>]
+ *    a.flatten(1  ) # => [0, 1, [2, 3], 4, 5, {foo: 0}, #<Set: {6, 7}>]
+ *    a.flatten(1.1) # => [0, 1, [2, 3], 4, 5, {foo: 0}, #<Set: {6, 7}>]
+ *    a.flatten(2)   # => [0, 1, 2, 3, 4, 5, {foo: 0}, #<Set: {6, 7}>]
+ *    a.flatten(3)   # => [0, 1, 2, 3, 4, 5, {foo: 0}, #<Set: {6, 7}>]
  *
  *  With +nil+ or negative +depth+, flattens all levels.
  *
- *    a.flatten     # => [0, 1, 2, 3, 4, 5, {:foo=>0}, #<Set: {6, 7}>]
- *    a.flatten(-1) # => [0, 1, 2, 3, 4, 5, {:foo=>0}, #<Set: {6, 7}>]
+ *    a.flatten     # => [0, 1, 2, 3, 4, 5, {foo: 0}, #<Set: {6, 7}>]
+ *    a.flatten(-1) # => [0, 1, 2, 3, 4, 5, {foo: 0}, #<Set: {6, 7}>]
  *
  *  Related: Array#flatten!;
  *  see also {Methods for Converting}[rdoc-ref:Array@Methods+for+Converting].