Was Scheme the first language to support closures?
Chapter 5: Fast-tracked delegates: 5.5.1
Last updated: 2/24/2008
Scheme was the first language to require closure semantics. It's possible that there were earlier Lisp dialects which implemented them to a greater or lesser extent - so perhaps my statement at the start of this section is overly bold. If you know of a language earlier than Scheme with closures in, please let me know so I can change this note accordingly...