Lindsey KuperOld research question: What is a correct emulator?
New research question after thinking about the old research question for a while: Oh god. Oh no. What is an emulator?
see also "compiler", "database", "runtime system" etc. etc.
Oliver Kennedy@lindsey Did you just repeat the same phrase four times?
Paul Cantrell@lindsey
Challenge: Come up with a definition of “emulator” under which a modern CPU isn’t an emulator that runs machine code on top of microcode
Challenge: Come up with a definition of “emulator” under which a modern CPU isn’t an emulator that runs machine code on top of microcode
Tabby
ShadSterling@inthehands @lindsey I tend to think of emulation as like mimicry; an emulator is something that behaves indistinguishably from the thing it emulates.
… tho by that definition every emulator is correct; if it’s not correct it’s only an attempted emulator
Ryan Brewer@lindsey I often see people start tumbling down this slope as soon as they start thinking about the word "transpiler" for two whole seconds haha. Coming out the other side we do the usual lazy natural language semantics approach, in my experience at least: an emulator is an element of the set of things most of us call emulators (😭)
@ryanbrewer oh god, I have a whole rant about "transpiler" https://decomposition.al/blog/2017/07/30/what-do-people-mean-when-they-say-transpiler/
What do people mean when they say “transpiler”?
A compiler is a computer program that takes a program as input, does some sort of transformation on it, and returns another program. Most of the time, we think of a compiler as something that translates code from a higher-level language (such as, for instance, Rust, Racket, or JavaScript) to a lower-level language (such as, for instance, LLVM IR or x86-64 assembly), but this doesn’t necessarily have to be the case.
Philippa Cowderoy@lindsey @ryanbrewer a transpiler is a compiler with impostor syndrome
bob@lindsey if you define a state space of all the I/O devices the emulator is emulating then a computer is an update function over that state space and an emulator is another equivalent computer. if you want timing equivalence then you can put wall timestamps in the state space
@bob obligatory link to https://recurse.social/@lindsey/115191815934445875
kaoudis
chris martens
Paul Hoffman@lindsey You seem caught up on the word "is".
Joshua Wise@lindsey 'What, if anything, is an emulator?'
@joshua This, but with "transpiler", is also what you commented on my blog post complaining about the word "transpiler" nine years ago
@lindsey The worst part of that is that I did not even get that snowclone from the original "what, if anything, is a parrot", but instead, I got it from @tom7 's classic, https://tom7.org/papers/epsilon.pdf , which must have been relatively fresh in my mind at the time
@joshua @tom7 @lindsey this meme has its roots in animal taxonomy! see "what, if anything, is a rabbit" (wood 1957) https://www.jstor.org/stable/2406062?seq=1
@joshua @tom7 @lindsey okay so i'm now going down a rabbit hole (whatever THAT is) trying to trace who got what from where. i THOUGHT surely tom must have heard of it through bob, via "what, if anything, is a programming paradigm" https://www.cs.cmu.edu/~rwh/papers/paradigms/paradigm.pdf but it looks like epsilon predates that by 3 years (epsilon does not cite a predecessor for the title)
@joshua @tom7 @lindsey meanwhile, *Bob* cites Jay Gould (1983), "what, if anything, is a zebra." but *Gould* https://emilkirkegaard.dk/en/wp-content/uploads/SJ-Gould-What-if-anything-is-a-zebra.pdf cites Wood (1957), "what, if anything is a rabbit". afaict the chain of allusion stops there
Tom VII 7th@chrisamaphone @joshua @lindsey yes, definitely from Bob, and the paper I know is the zebra one (pretty cool paper!) Good point on citations, though I’ll also note that when it comes to jokey allusions, the joke is better if you don’t have to explain it! Maybe a “spoilers” bibliography with red overprint so you have to use that red cellophane magnifying glass that comes with The Colonel’s Bequest