neonumeric - C++ arbitrary precision arithmetic library

[Chris Angelico]

On Sun, Mar 7, 2021 at 9:42 AM Mirko via Python-list
<python-list at python.org> wrote:
> I even wonder why they have tried. Writing a universal
> compiler/interpreter sounds logically impossible to me, Here's a
> simple Python expression:
>
> >>> 3+3*5
> 18
>
> And here's the same expression in (GNU) Smalltalk:
>
> st> 3+3*5
> 30
>
>
> How would such a universal compiler know which evaluation strategy
> to follow, if not by writing a parser end evaluator for every
> supported language? And if it's hard for this simple problem, how
> about more complex cases.

There are two ways in which "universal compiler/interpreter" can
definitely make sense, but neither of them is what he's trying to do.

1) A bytecode or machine code that all other languages can be compiled
to. For example, I'm running an amd64 CPU, so on this computer,
everything ultimately gets executed as amd64 bytecode. It's also
possible to have higher level bytecodes, or even textual languages
(Asm.js can be used as a compilation target).

2) "Compiler compilers" and grammar parsers. These are an excellent
tool for people designing programming language compilers, as they make
it a lot easier to describe the syntax and semantics for the language.

Both of them are tools that programming language developers use. They
don't replace language interpreters any more than a JSON parser
replaces the need to open files.

ChrisA