Definition:Real Interval/Notation/Wirth

Definition
The notation used on this site to denote a real interval is a fairly recent innovation, and was introduced by C.A.R. Hoare and Lyle Ramshaw:

The term Hoare-Ramshaw notation has consequently been coined by.

General Ordered Set
The notation applies to the general ordered set:

This double dots notation has a worthy precedent in the sphere of computer languages.

For example, Pascal and Haskell use the same notation for a closed interval.