# Range

Defines a range.

A range represents a sequence of one or many, ascending or descending, consecutive integers.

Ranges can be either increasing (`first <= last`

) or decreasing (`first > last`

). Ranges are also always inclusive.

A range is represented internally as a struct. However, the most common form of creating and matching on ranges is via the `../2`

macro, auto-imported from `Kernel`

:

iex> range = 1..3
1..3
iex> first..last = range
iex> first
1
iex> last
3

A range implements the `Enumerable`

protocol, which means functions in the `Enum`

module can be used to work with ranges:

iex> range = 1..10
1..10
iex> Enum.reduce(range, 0, fn i, acc -> i * i + acc end)
385
iex> Enum.count(range)
10
iex> Enum.member?(range, 11)
false
iex> Enum.member?(range, 8)
true

Such function calls are efficient memory-wise no matter the size of the range. The implementation of the `Enumerable`

protocol uses logic based solely on the endpoints and does not materialize the whole list of integers.

# Summary

## Types

- t()
- t(first, last)

## Functions

- disjoint?(range1, range2)
Checks if two ranges are disjoint.

- new(first, last)
Creates a new range.

# Types

# t()

t() :: %Range{first: integer(), last: integer()}

# t(first, last)

t(first, last) :: %Range{first: first, last: last}

# Functions

# disjoint?(range1, range2)

(since 1.8.0)
disjoint?(t(), t()) :: boolean()

Checks if two ranges are disjoint.

#### Examples

iex> Range.disjoint?(1..5, 6..9)
true
iex> Range.disjoint?(5..1, 6..9)
true
iex> Range.disjoint?(1..5, 5..9)
false
iex> Range.disjoint?(1..5, 2..7)
false

# new(first, last)

new(integer(), integer()) :: t()

Creates a new range.