olemus
programmi täitmist kirjeldav semantika
= a mathematical model of programming language execution

ülevaateid
https://en.wikipedia.org/wiki/Operational_semantics

https://book.huihoo.com/programming-languages/book/html/mainch4.html

https://homepage.divms.uiowa.edu/~slonnegr/plf/Book/Chapter8.pdf

http://pages.di.unipi.it/corradini/Didattica/PR2-B-14/OpSem.pdf