Looking for an interactive 6502 assembler

As a fan of Ruby, I would love to have something within the vein of IRB to quickly test my code
so that I can rapidly learn the language.

I've messed around with apple ii emulators and seen videos on youtube where you can quickly write
to memory and test your code.

Oddly enough, I haven't found a modern assembler that works that way. Obviously, I'm not running a
native 6502 environment like the C64 or Apple ii, but that doesn't mean much with modern virtual systems.

Anyway, perhaps someone here has such a tool in their arsenal? I suppose if enough time goes by,
I could write something myself, but I'm more focused on actual game making.

Thanks.

Listing lines and stuff is much harder to do anything in, if that's what you mean. Notepad programs are best way to work with code outside of unobtrusive IDE's. I dunno what to tell ya. Get started writing one I guess.

Try the 6502 macroassembler.
A small guide I wrote about it.
Not sure if that's quite in the vein you're looking for, but you can write, and run pretty immediately as well as step through it.

Thank you, I've been using this lately actually. I'm just set in my Linux / Commandline ways
Glad to see you you've written docs for it, for some reason I didn't have any when I downloaded it.