Xah Edict of the Day: anyone using the term REPL is to be despised upon immediately.
How should one call REPL then?
command-line user interface (CLUI)
Why should one call it CLUI?
Because, first of all, you are a Idiot. That's what that “I” is for. And U don't have a Clue. That's the CLU is for.
It's called CLUI because that's what it is.
REPL is like calling a car “Gas Combust Crank Run”. It's fashionable because you are a Tech Geeker and delights in jargon to hint your in-group status.
there's some bit of linguistic interest here. Note the phrase “read eval print loop”. A unix shell, is REPL, yet nobody calls it that, but “shell”. While, programing language's command line interface, are usually called REPL. Also, note that the phrase was popularized by functional language Scheme Lisp, notably by the book 《Structure and Interpretation of Computer Programs》 amazon The phrase REPL started to become popular in late 2000s, because many programing languages, started to have a interactive command line interface (⁖ Python, Ruby, Clojure, Scala), and it is fashionable to call it REPL because it showcase that the lang has functional programing language feature, which itself became popular due to CPU speed running out of juice. 〔☛ Guy Steele on Parallel Programing: Get rid of cons!〕
The term “shell” itself became popular for this reason. It was associated with “unix” back in 1980s and was the cool kid on the block.