[jepler]

A modest proposal: stop adopting new digraphs like [:, ^^, [[.

Unicode has at least 50 sets of pairing punctuation just waiting for use...

       \N{MEDIUM LEFT-POINTING ANGLE BRACKET ORNAMENT} U+276c 
       \N{HEAVY LEFT-POINTING ANGLE BRACKET ORNAMENT} U+2770 
       \N{LIGHT LEFT TORTOISE SHELL BRACKET ORNAMENT} U+2772 
       \N{MEDIUM LEFT CURLY BRACKET ORNAMENT} U+2774 

and multiple blocks of mathematical operators including

      ⊥ \N{UP TACK} U+22a5 ⊥
      ⊦ \N{ASSERTION} U+22a6 ⊦
      ⊧ \N{MODELS} U+22a7 ⊧
      ⊨ \N{TRUE} U+22a8 ⊨
      ⊩ \N{FORCES} U+22a9 ⊩

so you could just write the much clearer and more distinctive ⹗derive<serde::Serialize>⹘ and so on for the other new multi-punctuation sequences.

Yes, by the time C++37 comes around it might be necessary to petition Unicode to add additional code points. This wouldn't be a problem, for two reasons:

First, Unicode is accustomed to adding new code points and might even be willing to pre-allocate some entire pages to the C++ committee.

Second, the existing ways to modify emoji could apply to designated mathematical modifiers as well. For instance, ∅ would denote a distinct future C++ operator symbol from ∅ or ∅ (sadly, as of 2024, hacker news can't render "pale woman "A-type" empty set" or the other empty set symbol variations I lovingly entered in this paragraph).

These sequences are highly preferable to ASCII sequences like [: because the ZWJs allow supporting editors to correctly render them as a single glyph occupying a single terminal cell and without using font ligature hacks.

[Filligree]

Your serde example isn’t even rendering in my browser. It’s also missing from my keyboard; how do you propose I type it?

[greenavocado]

This isn't extreme enough. We need to use APL specific keyboards and write in APL for maximum clarity

https://xpqz.github.io/learnapl/intro.html

[zarzavat]

Lean (and iirc Mathematica) use backslash escapes: you type \symbolname and the symbol is inserted by your editor.

You can also imbue the backslash escape sequence with the same meaning as the unicode, so that in the event that the editor didn’t make this replacement it would still mean the same thing.

[layer8]

The most general solution is to configure yourself a Compose key [0]. Useful for typing anything that doesn’t directly figure on your keyboard.

[0] https://en.wikipedia.org/wiki/Compose_key

[98469056]

thats the joke

[fanf2]

One of the fun things about the Unicode bidi algorithm is that it flips brackets. You always use ( as an open round bracket, but if your script is rtl it appears like ). In order to support this feature, Unicode has a list of all known kinds of reversible paired brackets.

https://www.unicode.org/Public/UNIDATA/BidiBrackets.txt

For extra fun, C++ < angle brackets > are, of course, not brackets.

[eximius]

Is this satire? It has to be, right?

[omoikane]

This reminds me of Bjarne Stroustrup's proposal on overloading whitespace, and around page 4 he suggested using the full Unicode character set:

https://www.stroustrup.com/whitespace98.pdf

This was an April Fool's joke:

https://www.stroustrup.com/whitespace.html

I am not sure about the parent comment.