Comparable(T)
The Comparable mixin is used by classes whose objects may be ordered.
Including types must provide an <=> method, which compares the receiver against
another object, returning:
- a negative number if
selfis less than the other object - a positive number if
selfis greater than the other object 0ifselfis equal to the other objectnilifselfand the other object are not comparable
Comparable uses <=> to implement the conventional comparison operators
(<, <=, ==, >=, and >). All of these return false when <=>
returns nil.
Note that returning nil is only useful when defining a partial comparable
relationship. One such example is float values: they are generally comparable,
except for NaN. If none of the values of a type are comparable between each
other, Comparable shouldn't be included.
NOTE: When nil is returned from <=>, Array#sort and related sorting
methods will perform slightly slower.
Instance methods
Compares this object to other based on the receiver’s <=> method,
returning true if it returns a negative number.
Compares this object to other based on the receiver’s <=> method,
returning true if it returns a value equal or less then 0.
The comparison operator. Returns 0 if the two objects are equal,
a negative number if this object is considered less than other,
a positive number if this object is considered greater than other,
or nil if the two objects are not comparable.
Subclasses define this method to provide class-specific ordering.
The comparison operator is usually used to sort values:
# Sort in a descending way:
[3, 1, 2].sort { |x, y| y <=> x } # => [3, 2, 1]
# Sort in an ascending way:
[3, 1, 2].sort { |x, y| x <=> y } # => [1, 2, 3]
Compares this object to other based on the receiver’s <=> method,
returning true if it returns 0.
Also returns true if this and other are the same object.
Compares this object to other based on the receiver’s <=> method,
returning true if it returns a value greater then 0.
Compares this object to other based on the receiver’s <=> method,
returning true if it returns a value equal or greater than 0.
Clamps a value between min and max.
5.clamp(10, 100) # => 10
50.clamp(10, 100) # => 50
500.clamp(10, 100) # => 100
5.clamp(10, nil) # => 10
50.clamp(10, nil) # => 50
5.clamp(nil, 10) # => 5
50.clamp(nil, 10) # => 10