Do you get a lot of spam? I imagine ' @gmail.com' is one of the easiest and quickest emails to sign up for something with if you don't really care for the service. Maybe more of an older thing before verification emails were common

> I was here before the first character was carved into stone and I will be here when the last photon is emitted.

Primordial love and ultimate intellect.

Only those elements time cannot wear,

were made before me, and beyond time I stand.

Ah, a whitespace supremacist!

Guys that grew up with the 8-bit micros did write the spec—the first design drafts of the standard started circulating in 1988, version 1.0 came out in 1991. Given IBM’s primary role in the whole thing, even parents of such guys could’ve been involved.

The problem was, they had to sell their invention to other guys that had grown up with 8-bit micros and in the meantime had gotten very attached to their specific 8-bit encodings, so they had to make a lot of compromises: first 128 characters match ASCII; first 256 characters match Latin-1; alphabets encoded in order; codepoint-to-codepoint transcoding from any (reasonable) legacy encoding; throw out enough stuff to not need more than 2^16 characters. They were also racing against time, because in the meanwhile ISO was cooking up 10646, the Universal Character Set, built around ISO 2022’s teletype-inspired architecture of charset switching, and that only got killed because software vendors essentially declared a boycott and pointed to Unicode instead.

The result came out rather awkward as well as fairly expensive, and a lot of the promises needed to be broken afterwards anyway. But they’d have no users had they had done things differently. (Meanwhile, the UCS as initially conceived lacked such advanced operations as string equality.)

I don't follow? If bit 5 == zero meant "this is whitespace", then white-space characters would take up fully half of the unicode space. There would be more than 2 billion of them, not 32. Seems a bit overkill...

That wouldn't work. As the "Nothing is set in stone" section points out, in Unicode 6.2 the MONGOLIAN VOWEL SEPARATOR went from space separator to a format character.

No branching (if statements), no heavy CPU operations, just a multiplication by a constant, a shift and a lookup in a small table that will get cached fast

> Why is the hashing needed and how is it faster than a regex? Can someone smarter than me explain?

It's a perfect hash (i.e. no collisions) that hash to an entry in a 32-element array.

Very similar to how we usually do quick lookups of strings for `switch()` statements: https://github.com/lelanthran/libxtree/blob/878cb4fc11ffd617...

You need a hashtable to check whether this character is part of a given set. And the perfect hashing-based implementation is the most efficient form of a hashtable since you only need a lookup and an equality check. I included a small visualisation in the article that illustrates how it works, so if you try clicking on the elements, it will show you how the calculations are made.

How do you think regular expressions are implemented...?

My tab renders as: " > ". I still consider it whitespace.

What turns into whitespace due to rendering? Just because my font lacks that symbol doesn't mean it is whitespace.

I don't think you can "just render it" to figure out it's whitespace?

As the section "What is whitespace, anyway?" points out, if you render an OGHAM SPACE MARK in a font with a stemline you'll get a visible horizontal line.

The article covers that:

    The odd one out above is NEXT LINE (U+0085). Unicode explicitly includes it in White_Space, and Python accepts it too, but JavaScript doesn't. Instead, JavaScript recognises ZERO WIDTH NO-BREAK SPACE (U+FEFF), which Unicode doesn't include in the set.