diff --git a/array.c b/array.c
index b159ae70f0..2f14194e43 100644
--- a/array.c
+++ b/array.c
@@ -658,9 +658,8 @@ ary_ensure_room_for_push(VALUE ary, long add_len)
  *  Freezes +self+; returns +self+:
  *    a = []
  *    a.frozen? # => false
- *    a1 = a.freeze
+ *    a.freeze
  *    a.frozen? # => true
- *    a1.equal?(a) # => true # Returned self
  *
  *  An attempt to modify a frozen \Array raises an exception:
  *    # Raises FrozenError (can't modify frozen Array: [:foo, "bar", 2]):
@@ -1005,8 +1004,6 @@ rb_ary_s_try_convert(VALUE dummy, VALUE ary)
  *
  *    a = Array.new(3, 'x')
  *    a # => ['x', 'x', 'x']
- *    a[1].equal?(a[0]) # => true # Identity check.
- *    a[2].equal?(a[0]) # => true # Identity check.
  *
  *  With a block and argument +size+,
  *  returns an \Array of the given size;
@@ -1224,9 +1221,7 @@ ary_take_first_or_last(int argc, const VALUE *argv, VALUE ary, enum ary_take_pos
  *
  *  Appends +object+ to +self+; returns +self+:
  *    a = [:foo, 'bar', 2]
- *    a1 = a << :baz
- *    a1 # => [:foo, "bar", 2, :baz]
- *    a1.equal?(a) # => true # Returned self
+ *    a << :baz # => [:foo, "bar", 2, :baz]
  *
  *  Appends +object+ as one element, even if it is another \Array:
  *
@@ -1274,9 +1269,7 @@ rb_ary_cat(VALUE ary, const VALUE *argv, long len)
  *
  *  Appends each argument in +objects+ to +self+;  returns +self+:
  *    a = [:foo, 'bar', 2]
- *    a1 = a.push(:baz, :bat)
- *    a1 # => [:foo, "bar", 2, :baz, :bat]
- *    a1.equal?(a) # => true # Returned self
+ *    a.push(:baz, :bat) # => [:foo, "bar", 2, :baz, :bat]
  *
  *  Appends each argument as one element, even if it is another \Array:
  *
@@ -1615,9 +1608,7 @@ ary_ensure_room_for_unshift(VALUE ary, int argc)
  *
  *  Prepends the given +objects+ to +self+:
  *    a = [:foo, 'bar', 2]
- *    a1 = a.unshift(:bam, :bat)
- *    a1 # => [:bam, :bat, :foo, "bar", 2]
- *    a1.equal?(a) # => true # Returned self
+ *    a.unshift(:bam, :bat) # => [:bam, :bat, :foo, "bar", 2]
  */
 
 static VALUE
@@ -2473,9 +2464,7 @@ rb_ary_aset(int argc, VALUE *argv, VALUE ary)
  *  When +index+ is non-negative, inserts all given +objects+
  *  before the element at offset +index+:
  *    a = [:foo, 'bar', 2]
- *    a1 = a.insert(1, :bat, :bam)
- *    a # => [:foo, :bat, :bam, "bar", 2]
- *    a1.object_id == a.object_id # => true
+ *    a.insert(1, :bat, :bam) # => [:foo, :bat, :bam, "bar", 2]
  *
  *  Extends the array if +index+ is beyond the array (<tt>index >= self.size</tt>):
  *    a = [:foo, 'bar', 2]
@@ -2550,8 +2539,7 @@ ary_enum_length(VALUE ary, VALUE args, VALUE eobj)
  *  When a block given, passes each successive array element to the block;
  *  returns +self+:
  *    a = [:foo, 'bar', 2]
- *    a1 = a.each {|element|  puts "#{element.class} #{element}" }
- *    a1.equal?(a) # => true # Returned self
+ *    a.each {|element|  puts "#{element.class} #{element}" }
  *
  *  Output:
  *    Symbol foo
@@ -2604,8 +2592,7 @@ rb_ary_each(VALUE ary)
  *  When a block given, passes each successive array index to the block;
  *  returns +self+:
  *    a = [:foo, 'bar', 2]
- *    a1 = a.each_index {|index|  puts "#{index} #{a[index]}" }
- *    a1.equal?(a) # => true # Returned self
+ *    a.each_index {|index|  puts "#{index} #{a[index]}" }
  *
  *  Output:
  *    0 foo
@@ -2658,8 +2645,7 @@ rb_ary_each_index(VALUE ary)
  *  When a block given, passes, in reverse order, each element to the block;
  *  returns +self+:
  *    a = [:foo, 'bar', 2]
- *    a1 = a.reverse_each {|element|  puts "#{element.class} #{element}" }
- *    a1.equal?(a) # => true # Returned self
+ *    a.reverse_each {|element|  puts "#{element.class} #{element}" }
  *
  *  Output:
  *    Integer 2
@@ -2992,9 +2978,7 @@ rb_ary_to_s(VALUE ary)
  *
  *  When +self+ is an instance of \Array, returns +self+:
  *    a = [:foo, 'bar', 2]
- *    a.instance_of?(Array) # => true
- *    a1 = a.to_a
- *    a1.equal?(a) # => true # Returned self
+ *    a.to_a # => [:foo, "bar", 2]
  *
  *  Otherwise, returns a new \Array containing the elements of +self+:
  *    class MyArray < Array; end
@@ -3083,8 +3067,7 @@ rb_ary_to_h(VALUE ary)
  *
  *  Returns +self+:
  *    a = [:foo, 'bar', 2]
- *    a1 = a.to_ary
- *    a1.equal?(a) # => true # Returned self
+ *    a.to_ary # => [:foo, "bar", 2]
  */
 
 static VALUE
@@ -3125,9 +3108,7 @@ rb_ary_reverse(VALUE ary)
  *
  *  Reverses +self+ in place:
  *    a = ['foo', 'bar', 'two']
- *    a1 = a.reverse!
- *    a1 # => ["two", "bar", "foo"]
- *    a1.equal?(a) # => true # Returned self
+ *    a.reverse! # => ["two", "bar", "foo"]
  */
 
 static VALUE
@@ -3214,9 +3195,7 @@ rb_ary_rotate(VALUE ary, long cnt)
  *
  *  When no argument given, rotates the first element to the last position:
  *    a = [:foo, 'bar', 2, 'bar']
- *    a1 = a.rotate!
- *    a1 # => ["bar", 2, "bar", :foo]
- *    a1.equal?(a1) # => true # Retruned self
+ *    a.rotate! # => ["bar", 2, "bar", :foo]
  *
  *  ---
  *
@@ -3814,9 +3793,7 @@ rb_ary_collect(VALUE ary)
  *  Calls the block, if given, with each element;
  *  replaces the element with the block's return value:
  *    a = [:foo, 'bar', 2]
- *    a1 = a.collect! { |element| element.class }
- *    a1 # => [Symbol, String, Integer]
- *    a1.equal?(a) # => true # Returned self
+ *    a.collect! { |element| element.class } # => [Symbol, String, Integer]
  *
  *  ---
  *
@@ -4043,9 +4020,7 @@ select_bang_ensure(VALUE a)
  *
  *  Returns +self+ if any elements were removed:
  *    a = [:foo, 'bar', 2, :bam]
- *    a1 = a.select! {|element| element.to_s.start_with?('b') }
- *    a1 # => ["bar", :bam]
- *    a1.equal?(a) # => true # Returned self
+ *    a.select! {|element| element.to_s.start_with?('b') } # => ["bar", :bam]
  *
  *  Returns +nil+ if no elements were removed.
  *
@@ -4077,9 +4052,7 @@ rb_ary_select_bang(VALUE ary)
  *  Retains those elements for which the block returns a truthy value;
  *  deletes all other elements; returns +self+:
  *    a = [:foo, 'bar', 2, :bam]
- *    a1 = a.keep_if {|element| element.to_s.start_with?('b') }
- *    a1 # => ["bar", :bam]
- *    a1.equal?(a) # => true # Returned self
+ *    a.keep_if {|element| element.to_s.start_with?('b') } # => ["bar", :bam]
  *
  *  Returns a new \Enumerator if no block given:
  *    a = [:foo, 'bar', 2, :bam]
@@ -4121,9 +4094,8 @@ ary_resize_smaller(VALUE ary, long len)
  *  returns the last deleted element:
  *    s1 = 'bar'; s2 = 'bar'
  *    a = [:foo, s1, 2, s2]
- *    deleted_obj = a.delete('bar')
+ *    a.delete('bar') # => "bar"
  *    a # => [:foo, 2]
- *    deleted_obj.equal?(s2) # => true # Returned self
  *
  *  Returns +nil+ if no elements removed.
  *
@@ -4138,7 +4110,6 @@ ary_resize_smaller(VALUE ary, long len)
  *    a = [:foo, s1, 2, s2]
  *    deleted_obj = a.delete('bar') {|obj| fail 'Cannot happen' }
  *    a # => [:foo, 2]
- *    deleted_obj.object_id == s2.object_id # => true
  *
  *  If no such elements are found, returns the block's return value:
  *    a = [:foo, 'bar', 2]
@@ -4455,9 +4426,7 @@ ary_reject_bang(VALUE ary)
  *
  *  Returns +self+ if any elements removed:
  *    a = [:foo, 'bar', 2, 'bat']
- *    a1 = a.reject! {|element| element.to_s.start_with?('b') }
- *    a1 # => [:foo, 2]
- *    a1.equal?(a) # => true # Returned self
+ *    a.reject! {|element| element.to_s.start_with?('b') } # => [:foo, 2]
  *
  *  Returns +nil+ if no elements removed.
  *
@@ -4509,9 +4478,7 @@ rb_ary_reject(VALUE ary)
  *  Removes each element in +self+ for which the block returns a truthy value;
  *  returns +self+:
  *    a = [:foo, 'bar', 2, 'bat']
- *    a1 = a.delete_if {|element| element.to_s.start_with?('b') }
- *    a1 # => [:foo, 2]
- *    a1.equal?(a) # => true # Returned self
+ *    a.delete_if {|element| element.to_s.start_with?('b') } # => [:foo, 2]
  *
  *  Returns a new \Enumerator if no block given:
  *    a = [:foo, 'bar', 2]
@@ -4726,9 +4693,7 @@ rb_ary_transpose(VALUE ary)
  *
  *  Replaces the content of +self+ with the content of +other_array+:
  *    a = [:foo, 'bar', 2]
- *    a1 = a.replace(['foo', :bar, 3])
- *    a1 # => ["foo", :bar, 3]
- *    a1.equal?(a) # => true # Returned self
+ *    a.replace(['foo', :bar, 3]) # => ["foo", :bar, 3]
  *
  *  Ignores the size of +self+:
  *
@@ -4783,8 +4748,7 @@ rb_ary_replace(VALUE copy, VALUE orig)
  *
  *  Removes all elements from +self+:
  *    a = [:foo, 'bar', 2]
- *    a1 = a.clear
- *    a1.equal?(a) # => true # Returned self
+ *    a.clear # => []
  */
 
 VALUE
@@ -4829,9 +4793,7 @@ rb_ary_clear(VALUE ary)
  *  With argument +obj+ and no block given, replaces all elements with that one object:
  *    a = ['a', 'b', 'c', 'd']
  *    a # => ["a", "b", "c", "d"]
- *    a1 = a.fill(:X)
- *    a1 # => [:X, :X, :X, :X]
- *    a.equal?(a) #  => true # Retrurned self
+ *    a.fill(:X) # => [:X, :X, :X, :X]
  *
  *  ---
  *
@@ -5115,9 +5077,7 @@ ary_append(VALUE x, VALUE y)
  *
  *  Adds to +array+ all elements from each array in +other_arrays+; returns +self+:
  *    a = [0, 1]
- *    a1 = a.concat([2, 3], [4, 5])
- *    a1 # => [0, 1, 2, 3, 4, 5]
- *    a1.equal?(a) # => true # Returned self
+ *    a.concat([2, 3], [4, 5]) # => [0, 1, 2, 3, 4, 5]
  *
  *  Returns +self+ unmodified if no arguments given:
  *    a = [0, 1]
@@ -5659,11 +5619,7 @@ rb_ary_diff(VALUE ary1, VALUE ary2)
  *    [0, 1, 2, 3].difference([3, 0], [1, 3]) # => [2]
  *    [0, 1, 2].difference([4]) # => [0, 1, 2]
  *
- *  Returns a copy of +self+ if no arguments given:
- *    a0 = [0, 1]
- *    a1 = a0.difference(*[])
- *    a1 # => [0, 1]
- *    a1.equal?(a0) # => false
+ *  Returns a copy of +self+ if no arguments given.
  *
  *  See also Array#-.
  */
@@ -5773,11 +5729,7 @@ rb_ary_and(VALUE ary1, VALUE ary2)
  *  Preserves order from +self+:
  *    [0, 1, 2].intersection([2, 1, 0]) # => [0, 1, 2]
  *
- *  Returns a copy of +self+ if no arguments given:
- *    a0 = [0, 1]
- *    a1 = a0.intersection(*[])
- *    a1 # => [0, 1]
- *    a1.equal?(a0) # => false
+ *  Returns a copy of +self+ if no arguments given.
  *
  *  See also Array#&.
  */
@@ -5875,11 +5827,7 @@ rb_ary_or(VALUE ary1, VALUE ary2)
  *    [0, 1, 1].union([2, 1], [3, 1]) # => [0, 1, 2, 3]
  *    [0, 1, 2, 3].union([3, 2], [1, 0]) # => [0, 1, 2, 3]
  *
- *  Returns a copy of +self+ if no arguments given:
- *    a0 = [0, 1]
- *    a1 = a0.union(*[])
- *    a1 # => [0, 1]
- *    a1.equal?(a0) # => false
+ *  Returns a copy of +self+ if no arguments given.
  *
  *  See also Array#|.
  */
@@ -6332,9 +6280,7 @@ push_value(st_data_t key, st_data_t val, st_data_t ary)
  *
  *  Returns +self+ if any elements removed:
  *    a = [0, 0, 1, 1, 2, 2]
- *    a1 = a.uniq!
- *    a1 # => [0, 1, 2]
- *    a1.equal?(a) # => true # Returned self
+ *    a.uniq! # => [0, 1, 2]
  *
  *  Returns +nil+ if no elements removed.
  *
@@ -6346,9 +6292,7 @@ push_value(st_data_t key, st_data_t val, st_data_t ary)
  *
  *  Returns +self+ if any elements removed:
  *    a = ['a', 'aa', 'aaa', 'b', 'bb', 'bbb']
- *    a1 = a.uniq! {|element| element.size }
- *    a1 # => ['a', 'aa', 'aaa']
- *    a1.equal?(a) # => true # Returned self
+ *    a.uniq! {|element| element.size } # => ['a', 'aa', 'aaa']
  *
  *  Returns +nil+ if no elements removed.
  */
@@ -6434,12 +6378,7 @@ rb_ary_uniq(VALUE ary)
  *
  *  Removes all +nil+ elements from +self+.
  *
- *  Returns +self+ if any elements removed:
- *    a = [nil, 0, nil, 1, nil, 2, nil]
- *    a1 = a.compact! # => [0, 1, 2]
- *    a1.equal?(a) # => true # Returned self
- *
- *  Returns +nil+ if no elements removed.
+ *  Returns +self+ if any elements removed, otherwise +nil+.
  */
 
 static VALUE
@@ -6640,9 +6579,7 @@ flatten(VALUE ary, int level)
  *
  *  With non-negative argument +level+, flattens recursively through +level+ levels:
  *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
- *    a1 = a.flatten!(1)
- *    a1 # => [0, 1, [2, 3], 4, 5]
- *    a1.equal?(a) # => true # Returned self
+ *    a.flatten!(1) # => [0, 1, [2, 3], 4, 5]
  *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
  *    a.flatten!(2) # => [0, 1, 2, 3, 4, 5]
  *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
@@ -7126,8 +7063,7 @@ rb_ary_permutation_size(VALUE ary, VALUE args, VALUE eobj)
  *
  *  Example:
  *    a = [0, 1, 2]
- *    a1 = a.permutation(2) {|permutation| p permutation }
- *    a1.equal?(a) # => true # Returned self
+ *    a.permutation(2) {|permutation| p permutation }
  *  Output:
  *    [0, 1]
  *    [0, 2]
@@ -7269,8 +7205,7 @@ rb_ary_combination_size(VALUE ary, VALUE args, VALUE eobj)
  *
  *  Example:
  *    a = [0, 1, 2]
- *    a1 = a.combination(2) {|combination| p combination }
- *    a1.equal?(a) # => true # Returned self
+ *    a.combination(2) {|combination| p combination }
  *  Output:
  *    [0, 1]
  *    [0, 2]
@@ -7406,8 +7341,7 @@ rb_ary_repeated_permutation_size(VALUE ary, VALUE args, VALUE eobj)
  *
  *  +n+ = 1:
  *    a = [0, 1, 2]
- *    a1 = a.repeated_permutation(1) {|permutation| p permutation }
- *    a1.equal?(a) # => true # Returned self
+ *    a.repeated_permutation(1) {|permutation| p permutation }
  *  Output:
  *    [0]
  *    [1]
@@ -7535,8 +7469,7 @@ rb_ary_repeated_combination_size(VALUE ary, VALUE args, VALUE eobj)
  *
  *  +n+ = 1:
  *    a = [0, 1, 2]
- *    a1 = a.repeated_combination(1) {|combination| p combination }
- *    a1.equal?(a) # => true # Returned self
+ *    a.repeated_combination(1) {|combination| p combination }
  *  Output:
  *    [0]
  *    [1]
diff --git a/hash.c b/hash.c
index 76b521cb21..1594e84c97 100644
--- a/hash.c
+++ b/hash.c
@@ -1946,10 +1946,7 @@ rb_check_hash_type(VALUE hash)
  *    row.respond_to?(:to_hash)  # => true
  *    Hash.try_convert(row) # => {"Name"=>"Bob", "Age"=>45}
  *
- *  Returns the given <tt>obj</tt> if it is a Hash:
- *    h = {}
- *    h1 = Hash.try_convert(h)
- *    h1.equal?(h) # => true # Identity check
+ *  Returns the given <tt>obj</tt> if it is a Hash.
  *
  *  Returns <tt>nil</tt> unless <tt>obj.respond_to?(:to_hash)</tt>.
  *
@@ -2600,16 +2597,12 @@ hash_enum_size(VALUE hash, VALUE args, VALUE eobj)
  *  deletes each entry for which the block returns a truthy value;
  *  returns +self+:
  *    h = {foo: 0, bar: 1, baz: 2}
- *    h1 = h.delete_if { |key, value| value > 0 }
- *    h1 # => {:foo=>0}
- *    h1.equal?(h) # => true #  Identity check
+ *    h.delete_if { |key, value| value > 0 } # => {:foo=>0}
  *
  *  If no block given, returns a new \Enumerator:
  *    h = {foo: 0, bar: 1, baz: 2}
  *    e = h.delete_if # => #<Enumerator: {:foo=>0, :bar=>1, :baz=>2}:delete_if>
- *    h1 = e.each { |key, value| value > 0 }
- *    h1 # => {:foo=>0}
- *    h1.equal?(h) # => true #  Identity check
+ *    e.each { |key, value| value > 0 } # => {:foo=>0}
  *
  *  ----
  *
@@ -2638,18 +2631,14 @@ rb_hash_delete_if(VALUE hash)
  *  Returns +self+, whose remaining entries are those
  *  for which the block returns +false+ or +nil+:
  *    h = {foo: 0, bar: 1, baz: 2}
- *    h1 = h.reject! {|key, value| value < 2 }
- *    h1 # => {:baz=>2}
- *    h1.equal?(h) # => true # Identity check
+ *    h.reject! {|key, value| value < 2 } # => {:baz=>2}
  *
  *  Returns +nil+ if no entries are removed.
  *
  *  Returns a new \Enumerator if no block given:
  *    h = {foo: 0, bar: 1, baz: 2}
  *    e = h.reject! # => #<Enumerator: {:foo=>0, :bar=>1, :baz=>2}:reject!>
- *    h1 = e.each {|key, value| key.start_with?('b') }
- *    h1 # => {:foo=>0}
- *    h1.equal?(h) # => true # Identity check
+ *    e.each {|key, value| key.start_with?('b') } # => {:foo=>0}
  *
  *  ---
  *
@@ -2725,9 +2714,7 @@ rb_hash_reject(VALUE hash)
  *
  *  Returns a new \Hash object containing the entries for the given +keys+:
  *    h = {foo: 0, bar: 1, baz: 2}
- *    h1 = h.slice(:baz, :foo)
- *    h1 # => {:baz=>2, :foo=>0}
- *    h1.equal?(h) # => false
+ *    h.slice(:baz, :foo) # => {:baz=>2, :foo=>0}
  *
  *  The given keys that are not found are ignored:
  *    h = {foo: 0, bar: 1}
@@ -2820,9 +2807,7 @@ rb_hash_values_at(int argc, VALUE *argv, VALUE hash)
  *    h = {foo: 0, bar: 1, baz: 2}
  *    h.fetch_values(:baz, :foo) # => [2, 0]
  *
- *  Returns a new empty \Array if no arguments given:
- *    h = {foo: 0, bar: 1, baz: 2}
- *    h.fetch_values # => []
+ *  Returns a new empty \Array if no arguments given.
  *
  *  When a block given, calls the block with each missing key,
  *  treating the block's return value as the value for that key:
@@ -2869,16 +2854,12 @@ select_i(VALUE key, VALUE value, VALUE result)
  *
  *  Returns a new \Hash object whose entries are those for which the block returns a truthy value:
  *    h = {foo: 0, bar: 1, baz: 2}
- *    h1 = h.select {|key, value| value < 2 }
- *    h1 # => {:foo=>0, :bar=>1}
- *    h1.equal?(h) # => false
+ *    h.select {|key, value| value < 2 } # => {:foo=>0, :bar=>1}
  *
  *  Returns a new \Enumerator if no block given:
  *    h = {foo: 0, bar: 1, baz: 2}
  *    e = h.select # => #<Enumerator: {:foo=>0, :bar=>1, :baz=>2}:select>
- *    h1 = e.each {|key, value| value < 2 }
- *    h1 # => {:foo=>0, :bar=>1}
- *    h1.equal?(h) # => false
+ *    e.each {|key, value| value < 2 } # => {:foo=>0, :bar=>1}
  *
  *  ---
  *
@@ -2921,18 +2902,14 @@ keep_if_i(VALUE key, VALUE value, VALUE hash)
  *
  *  Returns +self+, whose entries are those for which the block returns a truthy value:
  *    h = {foo: 0, bar: 1, baz: 2}
- *    h1 = h.select! {|key, value| value < 2 }
- *    h # => {:foo=>0, :bar=>1}
- *    h1.equal?(h) # => true
+ *    h.select! {|key, value| value < 2 }  => {:foo=>0, :bar=>1}
  *
  *  Returns +nil+ if no entries were removed.
  *
  *  Returns a new \Enumerator if no block given:
  *    h = {foo: 0, bar: 1, baz: 2}
  *    e = h.select!  # => #<Enumerator: {:foo=>0, :bar=>1, :baz=>2}:select!>
- *    h1 = e.each { |key, value| value < 2 }
- *    h1 # => {:foo=>0, :bar=>1}
- *    h1.equal?(h) # => true
+ *    e.each { |key, value| value < 2 } # => {:foo=>0, :bar=>1}
  *
  *  ---
  *
@@ -2965,16 +2942,12 @@ rb_hash_select_bang(VALUE hash)
  *  retains the entry if the block returns a truthy value;
  *  deletes the entry otherwise; returns +self+.
  *    h = {foo: 0, bar: 1, baz: 2}
- *    h1 = h.keep_if { |key, value| key.start_with?('b') }
- *    h1 # => {:bar=>1, :baz=>2}
- *    h1.object_id == h.object_id # => true
+ *    h.keep_if { |key, value| key.start_with?('b') } # => {:bar=>1, :baz=>2}
  *
  *  Returns a new \Enumerator if no block given:
  *    h = {foo: 0, bar: 1, baz: 2}
  *    e = h.keep_if # => #<Enumerator: {:foo=>0, :bar=>1, :baz=>2}:keep_if>
- *    h1 = e.each { |key, value| key.start_with?('b') }
- *    h1 # => {:bar=>1, :baz=>2}
- *    h1.object_id == h.object_id # => true
+ *    e.each { |key, value| key.start_with?('b') } # => {:bar=>1, :baz=>2}
  *
  *  Raises an exception if the block attempts to add a new key:
  *    h = {foo: 0, bar: 1, baz: 2}
@@ -3005,8 +2978,7 @@ clear_i(VALUE key, VALUE value, VALUE dummy)
  *
  *  Removes all hash entries; returns +self+:
  *    h = {foo: 0, bar: 1, baz: 2}
- *    h1 = h.clear # => {}
- *    h1.equal?(h) # => true # Identity check
+ *    h.clear # => {}
  */
 
 VALUE
@@ -3117,9 +3089,7 @@ rb_hash_aset(VALUE hash, VALUE key, VALUE val)
  *  Replaces the entire contents of +self+ with the contents of +other_hash+;
  *  returns +self+:
  *    h = {foo: 0, bar: 1, baz: 2}
- *    h1 = h.replace({bat: 3, bam: 4})
- *    h1 # => {:bat=>3, :bam=>4}
- *    h1.equal?(h) # => true # Identity check
+ *    h.replace({bat: 3, bam: 4}) # => {:bat=>3, :bam=>4}
  */
 
 static VALUE
@@ -3213,9 +3183,7 @@ each_value_i(VALUE key, VALUE value, VALUE _)
  *
  *  Calls the given block with each value; returns +self+:
  *    h = {foo: 0, bar: 1, baz: 2}
- *    h1 = h.each_value {|value| puts value }
- *    h1 # => {:foo=>0, :bar=>1, :baz=>2}
- *    h1.equal?(h) # => true # Identity check
+ *    h.each_value {|value| puts value } # => {:foo=>0, :bar=>1, :baz=>2}
  *  Output:
  *    0
  *    1
@@ -3261,9 +3229,7 @@ each_key_i(VALUE key, VALUE value, VALUE _)
  *
  *  Calls the given block with each key; returns +self+:
  *    h = {foo: 0, bar: 1, baz: 2}
- *    h1 = h.each_key {|key| puts key }
- *    h1 # => {:foo=>0, :bar=>1, :baz=>2}
- *    h1.equal?(h) # => true # Identity check
+ *    h.each_key {|key| puts key }  # => {:foo=>0, :bar=>1, :baz=>2}
  *  Output:
  *    foo
  *    bar
@@ -3318,11 +3284,9 @@ each_pair_i_fast(VALUE key, VALUE value, VALUE _)
  *    hash.each -> new_enumerator
  *    hash.each_pair -> new_enumerator
  *
- *  Calls the given block with each key-value pair, returning self:
+ *  Calls the given block with each key-value pair, returning +self+:
  *    h = {foo: 0, bar: 1, baz: 2}
- *    h1 = h.each_pair {|key, value| puts "#{key}: #{value}"}
- *    h1 # => {:foo=>0, :bar=>1, :baz=>2}
- *    h1.equal?(h) # => true # Identity check
+ *    h.each_pair {|key, value| puts "#{key}: #{value}"} # => {:foo=>0, :bar=>1, :baz=>2}
  *  Output:
  *    foo: 0
  *    bar: 1
@@ -3456,9 +3420,7 @@ static VALUE rb_hash_flatten(int argc, VALUE *argv, VALUE hash);
  *
  *  Returns +self+ with new keys provided by the block:
  *    h = {foo: 0, bar: 1, baz: 2}
- *    h1 = h.transform_keys! {|key| key.to_s }
- *    h1 # => {"foo"=>0, "bar"=>1, "baz"=>2}
- *    h1.equal?(h) # => true # Identity check
+ *    h.transform_keys! {|key| key.to_s } # => {"foo"=>0, "bar"=>1, "baz"=>2}
  *
  *  Overwrites values for duplicate keys:
  *    h = {foo: 0, bar: 1, baz: 2}
@@ -3579,9 +3541,7 @@ rb_hash_transform_values(VALUE hash)
  *
  *  Returns +self+, whose keys are unchanged, and whose values are determined by the given block.
  *    h = {foo: 0, bar: 1, baz: 2}
- *    h1 = h.transform_values! {|value| value * 100}
- *    h1 # => {:foo=>0, :bar=>100, :baz=>200}
- *    h1.equal?(h) # => true # Identity check
+ *    h.transform_values! {|value| value * 100} # => {:foo=>0, :bar=>100, :baz=>200}
  *
  *  Allows the block to add a new entry:
  *    h = {foo: 0, bar: 1, baz: 2}
@@ -3693,9 +3653,7 @@ rb_hash_inspect(VALUE hash)
  *
  *  Returns +self+:
  *    h = {foo: 0, bar: 1, baz: 2}
- *    h1 = h.to_hash
- *    h1 # => {:foo=>0, :bar=>1, :baz=>2}
- *    h1.equal?(h) # => true # Identity check
+ *    h.to_hash # => {:foo=>0, :bar=>1, :baz=>2}
  */
 static VALUE
 rb_hash_to_hash(VALUE hash)
@@ -3743,9 +3701,7 @@ rb_hash_to_h_block(VALUE hash)
  *
  *  For an instance of \Hash, returns +self+:
  *    h = {foo: 0, bar: 1, baz: 2}
- *    h1 = h.to_h
- *    h1 # => {:foo=>0, :bar=>1, :baz=>2}
- *    h1.equal?(h) #  => true # Identity check
+ *    h.to_h # => {:foo=>0, :bar=>1, :baz=>2}
  *
  *  For a subclass of \Hash, returns a new \Hash
  *  containing the content of +self+:
@@ -4253,8 +4209,7 @@ rb_hash_update_block_i(VALUE key, VALUE value, VALUE hash)
  *    h = {foo: 0, bar: 1, baz: 2}
  *    h1 = {bat: 3, bar: 4}
  *    h2 = {bam: 5, bat:6}
- *    h3 = h.merge!(h1, h2) # => {:foo=>0, :bar=>4, :baz=>2, :bat=>6, :bam=>5}
- *    h3.equal?(h) # => true # Identity check
+ *    h.merge!(h1, h2) # => {:foo=>0, :bar=>4, :baz=>2, :bat=>6, :bam=>5}
  *
  *  ---
  *
@@ -4272,7 +4227,6 @@ rb_hash_update_block_i(VALUE key, VALUE value, VALUE hash)
  *    h2 = {bam: 5, bat:6}
  *    h3 = h.merge!(h1, h2) { |key, old_value, new_value| old_value + new_value }
  *    h3 # => {:foo=>0, :bar=>5, :baz=>2, :bat=>9, :bam=>5}
- *    h3.equal?(h) # => true # Identity check
  *
  *  Allows the block to add a new key:
  *    h = {foo: 0, bar: 1, baz: 2}
@@ -4280,7 +4234,6 @@ rb_hash_update_block_i(VALUE key, VALUE value, VALUE hash)
  *    h2 = {bam: 5, bat:6}
  *    h3 = h.merge!(h1, h2) { |key, old_value, new_value| h[:new_key] = 10 }
  *    h3 # => {:foo=>0, :bar=>10, :baz=>2, :bat=>10, :new_key=>10, :bam=>5}
- *    h3.equal?(h) # => true # Identity check
  *
  *  ---
  *
@@ -4293,7 +4246,6 @@ rb_hash_update_block_i(VALUE key, VALUE value, VALUE hash)
  *    h.merge # => {:foo=>0, :bar=>1, :baz=>2}
  *    h1 = h.merge! { |key, old_value, new_value| raise 'Cannot happen' }
  *    h1 # => {:foo=>0, :bar=>1, :baz=>2}
- *    h1.equal?(h) # => true # Identity check
  */
 
 static VALUE
@@ -4392,9 +4344,7 @@ rb_hash_update_by(VALUE hash1, VALUE hash2, rb_hash_update_func *func)
  *    h = {foo: 0, bar: 1, baz: 2}
  *    h1 = {bat: 3, bar: 4}
  *    h2 = {bam: 5, bat:6}
- *    h3 = h.merge(h1, h2)
- *    h3 # => {:foo=>0, :bar=>4, :baz=>2, :bat=>6, :bam=>5}
- *    h3.equal?(h) # => false # Identity check
+ *    h.merge(h1, h2) # => {:foo=>0, :bar=>4, :baz=>2, :bat=>6, :bam=>5}
  *
  *  ---
  *
@@ -4412,7 +4362,6 @@ rb_hash_update_by(VALUE hash1, VALUE hash2, rb_hash_update_func *func)
  *    h2 = {bam: 5, bat:6}
  *    h3 = h.merge(h1, h2) { |key, old_value, new_value| old_value + new_value }
  *    h3 # => {:foo=>0, :bar=>5, :baz=>2, :bat=>9, :bam=>5}
- *    h3.equal?(h) # => false # Identity check
  *
  *  Ignores an attempt in the block to add a new key:
  *    h = {foo: 0, bar: 1, baz: 2}
@@ -4420,7 +4369,6 @@ rb_hash_update_by(VALUE hash1, VALUE hash2, rb_hash_update_func *func)
  *    h2 = {bam: 5, bat:6}
  *    h3 = h.merge(h1, h2) { |key, old_value, new_value| h[:new_key] = 10 }
  *    h3 # => {:foo=>0, :bar=>10, :baz=>2, :bat=>10, :bam=>5}
- *    h3.equal?(h) # => false # Identity check
  *
  *  ---
  *
@@ -4430,12 +4378,9 @@ rb_hash_update_by(VALUE hash1, VALUE hash2, rb_hash_update_func *func)
  *
  *  Example:
  *    h = {foo: 0, bar: 1, baz: 2}
- *    h1 = h.merge
+ *    h.merge # => {:foo=>0, :bar=>1, :baz=>2}
+ *    h1 = h.merge { |key, old_value, new_value| raise 'Cannot happen' }
  *    h1 # => {:foo=>0, :bar=>1, :baz=>2}
- *    h1.equal?(h) # => false # Identity check
- *    h2 = h.merge { |key, old_value, new_value| raise 'Cannot happen' }
- *    h2 # => {:foo=>0, :bar=>1, :baz=>2}
- *    h2.equal?(h) # => false # Identity check
  */
 
 static VALUE
@@ -4688,9 +4633,7 @@ rb_hash_compact(VALUE hash)
  *
  *  Returns +self+ with all its +nil+-valued entries removed (in place):
  *    h = {foo: 0, bar: nil, baz: 2, bat: nil}
- *    h1 = h.compact!
- *    h1 # => {:foo=>0, :baz=>2}
- *    h1.equal?(h) # => true
+ *    h.compact! # => {:foo=>0, :baz=>2}
  *
  *  Returns +nil+ if no entries were removed.
  */
@@ -4723,7 +4666,6 @@ static st_table *rb_init_identtable_with_size(st_index_t size);
  *  so +s1+ will overwrite +s0+:
  *    s0 = 'x'
  *    s1 = 'x'
- *    s0.equal?(s0) # => false
  *    h = {}
  *    h.compare_by_identity? # => false
  *    h[s0] = 0
@@ -4733,8 +4675,7 @@ static st_table *rb_init_identtable_with_size(st_index_t size);
  *  After calling \#compare_by_identity, the keys are considered to be different,
  *  and therefore do not overwrite each other:
  *    h = {}
- *    h1 = h.compare_by_identity # => {}
- *    h1.equal?(h) # => true
+ *    h.compare_by_identity # => {}
  *    h.compare_by_identity? # => true
  *    h[s0] = 0
  *    h[s1] = 1
@@ -5806,9 +5747,7 @@ env_keys(int raw)
  * The order of the names is OS-dependent.
  * See {About Ordering}[#class-ENV-label-About+Ordering].
  *
- * Returns the empty Array if ENV is empty:
- *   ENV.clear
- *   ENV.keys # => []
+ * Returns the empty Array if ENV is empty.
  */
 
 static VALUE
@@ -5893,9 +5832,7 @@ env_values(void)
  * The order of the values is OS-dependent.
  * See {About Ordering}[#class-ENV-label-About+Ordering].
  *
- * Returns the empty Array if ENV is empty:
- *   ENV.clear
- *   ENV.values # => []
+ * Returns the empty Array if ENV is empty.
  */
 static VALUE
 env_f_values(VALUE _)
@@ -6072,8 +6009,7 @@ env_delete_if(VALUE ehash)
  * Returns +nil+ in the Array for each name that is not an ENV name:
  *   ENV.values_at('foo', 'bat', 'bar', 'bam') # => ["0", nil, "1", nil]
  *
- * Returns an empty \Array if no names given:
- *   ENV.values_at() # => []
+ * Returns an empty \Array if no names given.
  *
  * Raises an exception if any name is invalid.
  * See {Invalid Names and Values}[#class-ENV-label-Invalid+Names+and+Values].
@@ -7135,7 +7071,6 @@ env_update(VALUE env, VALUE hash)
  *    h = {s => 0}
  *    first_key = h.keys.first
  *    first_key.frozen? # => true
- *    first_key.equal?(s) # => false
  *
  *  ==== User-Defined \Hash Keys
  *