### 2.34.1 Definition of an interval : `a1..a2`

An interval is represented by two real numbers
separated by `..`, for example

`1..3`

`1.2..sqrt(2)`

Input :

`A:=1..4`

`B:=1.2..sqrt(2)`

**Warning!**

The order of the boundaries of the interval is significant. For
example, if you input

`B:=2..3; C:=3..2`,

then `B` and `C` are different, `B==C` returns `0`.