read-eval-print loop (REPL)

The first time I have ever heard of "REPL" was in the previous Microsoft article.

I think it's a Lisp Terminology.

http://en.wikipedia.org/wiki/Read-eval-print_loop

This is basically a fancy way to say a Command Interpreter.  Nothing more fancy then any Boot load such as U-boot does, or Bash, DOS, BC, Basic, Lisp, Smalltalk, Standard ML, Perl, Prolog, Scala, Python, Ruby's IRB, Haskell, APL, BASIC, J, Tcl or the many other interpreters available.

C and C++

• cint - From Cern 
• c-repl
• ccons

Java

• BeanShell, not really Java syntax (Good for making sure the classes do what you want),
• Groovy

Perl

• Devel::REPL

Python

• PyPy a self-hosting interpreter
• Online Python Read-Eval-Print Loop (REPL)

If you have anything else to include please add a comment below.