[shakna]

> But if somebody believes that writing a transpiler isn’t fundamentally the same thing as writing a compiler,

I'd be surprised if anyone did.

The use of transpiler is more about audience expectation, a specificity.

It's shorter than writing "source-to-source compiler", and acknowledges compiler as its superset, right there in its name

[sjrd]

That's unfortunately not my experience. I'm appalled every time someone tells me "But Scala.js is not a compiler, it's a transpiler, since it compiles to JS!"

I assume other language users and authors suffer the same kind of comments on a regular basis.

[shakna]

I'm now horrified to learn that you experience is the norm.

And that the cognitive dissonance to say:

> ...is not a compiler, it's a transpiler, since it compiles to...

is alive and well.

Mea culpa.

[TeMPOraL]

Welcome to the webdev world. It keeps inventing new terms for things that already have established terms for decades, probably because it's rare anyone bothers to look back at the decades of stuff not done in JS...

[mseebach]

I'd argue that it's a compiler if it treats JS as a lower language - that the output is simply an intermediate artefact for executing Scala on a JS engine, and not meant for human consumption. If, on the other hand, the output is meant to be developed further by hand, if the output is considered an equivalent and not lower representation, then it's a transpiler.

[wtetzner]

> If, on the other hand, the output is meant to be developed further by hand, if the output is considered an equivalent and not lower representation, then it's a transpiler.

Which is also still a compiler.

[mseebach]

I would argue that it isn't, if it is, then what's the distinction between a compiler and a transpiler?

[yorwba]

If all birds are dinosaurs, then what's the distinction between a dinosaur and a bird? Well, there used to be dinosaurs who weren't birds.

Likewise, there are compilers I wouldn't call transpilers.

[mseebach]

So you suggest that transpilers are a subset of compilers, where I suggest that they are disjoint sets. No need for snark.

[tom_mellior]

> It's shorter than writing "source-to-source compiler"

Brevity isn't everything. But more importantly, "transpiler" (like "source-to-source compiler") does not say what you are compiling from, and what you are compiling to. In order for the term "transpiler" to be useful, you need to specify those things. Anything you think you imply by using the term is not, in fact, implied.

If you compare the lengths of "JavaScript to Pascal compiler" and "JavaScript to Pascal transpiler", you might be in for a surprise!

[TeMPOraL]

I think the current definition of "transpiler", the way it's used in the wild, means "compiles $something to JavaScript". I haven't seen anyone using this word for anything else than compiling to JS.

[shakna]

It may lack some specificity, but it makes you look for the terms for "from" and "to".

It eliminates bytecode compilers and native compilers from the conversation immediately.

> It's not a native compiler, it's a transpiler

If this was said, you wouldn't then ask if it compiled for a VM, or if it could directly produce small binaries.

I wouldn't say the term is completely redundant. Only when you introduce it for the first time.

E.g.

> That's not possible. It's a transpiler. Back to the topic at hand...