Range.size

You're seeing just the function size, go back to Range module for more information.
Link to this function

size(range)

View Source (since 1.12.0)

Returns the size of range.

Examples

iex> Range.size(1..10)
10
iex> Range.size(1..10//2)
5
iex> Range.size(1..10//3)
4
iex> Range.size(1..10//-1)
0

iex> Range.size(10..1)
10
iex> Range.size(10..1//-1)
10
iex> Range.size(10..1//-2)
5
iex> Range.size(10..1//-3)
4
iex> Range.size(10..1//1)
0