Architecture of Various Interpreters

• Bash and all shells I've looked at: lexer/parser -> AST -> tree interpreter.

  • (but note that they do dynamic parsing too)

• CPython: parser -> parse tree -> "transformer" -> AST -> compiler -> graph of bytecode objects -> bytecode assembler -> .pyc files -> bytecode interpreter.

• Lua: No tree representation! It constructs bytecode for a register machine while parsing. I believe this style came from Pascal compilers.

• R: It was a tree interpreter, but they added bytecode around 2011.

• Ruby: I believe the same is true; it was a tree interpreter, but they added bytecode.

• Next Generation Shell: PEG parser -> AST -> bytecode