At the time when IS-BASIC was being written, there was a new ANSI Standard being developed for BASIC, and IS-BASIC was based on the latest Standard proposals out at the time. It did not actually become a full Sandard until 1986 - a bit late for the Enterprise!
And a bit late for the rest of the computing world: at the time it looked as though it could become a "big thing", but history shows us that Microsoft BASIC dominated. Despite little use ANSI BASIC also became a European ECMA Standard, an ISO Standard (in 1991) and a Japanese JIS Standard (in 1993).
I have just discovered that it is sometimes also called "Full BASIC". Maybe everyone else knew this, but I did not!
![ds_icon_lol :lol:](/Smileys/phpbb/ds_icon_lol.gif)
There is a good history of the origins of Full BASIC and how it came about, and the problems in making it an ANSI Standard, on Wikipedia:
https://en.wikipedia.org/wiki/Full_BASIC.
I have also come across this interesting article from BYTE magazine, June 1982, "On The Way To Standard BASIC". Written before IS-BASIC was even started, it contains lots of code examples which will look familiar to EP users, and a few hints at things that did not make it into IS-BASIC!
http://enterprise.iko.hu/articles/BYTE_1982_06_On_the_Way_to_Standard_BASIC.pdf (thanks Zozosoft for hosting and making it readable)