diff --git a/array.c b/array.c
index 275ac006c2..b6768e52d3 100644
--- a/array.c
+++ b/array.c
@@ -3186,48 +3186,34 @@ rb_ary_rotate(VALUE ary, long cnt)
/*
* call-seq:
- * array.rotate! -> self
- * array.rotate!(count) -> self
+ * rotate!(count = 1) -> self
*
* Rotates +self+ in place by moving elements from one end to the other; returns +self+.
*
- * When no argument given, rotates the first element to the last position:
- *
- * a = [:foo, 'bar', 2, 'bar']
- * a.rotate! # => ["bar", 2, "bar", :foo]
- *
- * When given a non-negative Integer +count+,
+ * With non-negative numeric +count+,
* rotates +count+ elements from the beginning to the end:
*
- * a = [:foo, 'bar', 2]
- * a.rotate!(2)
- * a # => [2, :foo, "bar"]
+ * [0, 1, 2, 3].rotate!(2) # => [2, 3, 0, 1]
+ [0, 1, 2, 3].rotate!(2.1) # => [2, 3, 0, 1]
*
* If +count+ is large, uses count % array.size as the count:
*
- * a = [:foo, 'bar', 2]
- * a.rotate!(20)
- * a # => [2, :foo, "bar"]
+ * [0, 1, 2, 3].rotate!(21) # => [1, 2, 3, 0]
*
- * If +count+ is zero, returns +self+ unmodified:
+ * If +count+ is zero, rotates no elements:
*
- * a = [:foo, 'bar', 2]
- * a.rotate!(0)
- * a # => [:foo, "bar", 2]
+ * [0, 1, 2, 3].rotate!(0) # => [0, 1, 2, 3]
*
- * When given a negative Integer +count+, rotates in the opposite direction,
+ * With a negative numeric +count+, rotates in the opposite direction,
* from end to beginning:
*
- * a = [:foo, 'bar', 2]
- * a.rotate!(-2)
- * a # => ["bar", 2, :foo]
+ * [0, 1, 2, 3].rotate!(-1) # => [3, 0, 1, 2]
*
* If +count+ is small (far from zero), uses count % array.size as the count:
*
- * a = [:foo, 'bar', 2]
- * a.rotate!(-5)
- * a # => ["bar", 2, :foo]
+ * [0, 1, 2, 3].rotate!(-21) # => [3, 0, 1, 2]
*
+ * Related: see {Methods for Assigning}[rdoc-ref:Array@Methods+for+Assigning].
*/
static VALUE