I must confess some ignorance... I just became aware of the Scientific Vector Language (SVL) which has been around since 1994 and was created solely for computational chemistry.
It has a large database of modules/API/functions/scripts.
The group behind this language is the Chemical Computing Group. While they have competitors for their software which is the Molecular Operating Environment, which runs on SVL, I don't know if their competitors have gone so far as to develop their own programming language.
Are there other programming languages that have been developed specifically for computational chemistry that I am not aware of?