In general people have come to expect that hitting return once in a comment field on GitHub will produce a newline, having been the case for many years, so we try to preserve that expectation. Hence not changing the option being used when rendering comments.
Conversely, they don't expect the same from Markdown files stored in their repository (e.g. I put each sentence in a paragraph on its own line for my blog, for easier diffing and editing). Additionally, we couldn't normalise these documents even if we wanted (to prevent everything breaking by being over-vertically spaced). Hence not changing the option being not used in this case!
GFM itself leaves that line unchanged because we don't actually change that option in our implementation — the reference implementation `cmark` (which we built upon) supplies the "hardbreaks" option, described as follows:
> --hardbreaks Treat newlines as hard line breaks
We turn this option on when rendering issues, issue comments and so on, but leave it off when rendering blobs (such as README.md). Both are GFM, one just uses this option to make it more conducive to communication.
The fact that the CommentReader is dispatched from a table called "macros" (https://github.com/clojure/clojure/blob/master/src/jvm/cloju...) means nothing, unless you also call string literals "string macros", s-expressions "s-exp macros", etc., since mostly everything is dispatched from that table.
> the subset that it optimized for would still be C
This doesn't mean to imply the subset is the entirety of C; it means the subset is part of the definition of C — just like you can say "'int x = 4;' is C", even though it's a (demonstration of a) subset of C.
The JavaScript which happens to be optimised under the name "asm.js" is still JavaScript that executes in any non-optimising runtime, and the semantics with those optimisations and without are the same.
Fuck that noise. It's representative of a shit state of affairs when 'mastery' of one particular language is necessary to gain respect among fluent speakers. No respect for those who haven't 'mastered' the thing we have mastery of? Fuck, it sounds like a recipe for supremacy or something.