no, but it BECOMES javascript after transpile time
Yep. Just like C code isn't binary code.
Why is it not JavaScript? The Ecmascript spec explicitly allows syntax extensions.
I'm not javascript syntax, especially if you're being pedantic, but focusing on that is kind of missing the point, which is that it's tool friendly in the way string interpolation is not.
Is this valid Javascript: %%$$#~~~~##
What if I make it my special js "syntax extension"?