[marginalia_nu]

> If Rust is not to fizzle like Ada [...] it needs a radically faster adoption rate

I would challenge this. Adoption rate does not mean longevity. There are many flash-in-the-pan technologies that are here one year and gone a few later.

As a concrete example, the adoption rate of Ruby on Rails was nearly vertical in around 2006. PHP was old, boring, adoption was flat if not declining. ROR looked to become become king of the web. Today ROR is largely a legacy technology, a footnote at best. PHP is still here, though. It will likely outlast node, too, despite being an awful language.

Large-scale adoption is a slow march through the decades, and has a lot more with momentum than anything else. A big reason why these antique languages have such sticking power is that they have a mature and well-established ecosystem. If you want a new language to join them, that is where the focus should be.

[ncmncm]

The number of lines of code in use has to be high, but there is a great deal of COBOL code. Who is coding new COBOL, or PHP? Ruby looked promising, but fizzled. Sticking power is necessary, but not sufficient. Rapid increase is necessary, but not sufficient.

To get that miracle, you need both. Sticking at low adoption is the same as fizzling. Peaking but not sticking is fizzling. There are millions of ways to fail, a whole selection laid out for every language to choose from. Most languages pick one, and do. Succeeding takes a lot of good choices, and negligibly few bad ones. Failing to ease adoption where possible is a bad one.

[marginalia_nu]

There is definitely new PHP being written, COBOL is finally beginning to decline, but it will probably be around for quite some time still.

I wouldn't worry at all about what the adoption graph looks like. The only thing that matters is whether the language is worth adopting.

[ncmncm]

There have been many, many languages worth adopting. We don't use those because they were not, in the end, adopted enough.

[marginalia_nu]

It's not enough to merely be better than the previous languages, but you must be so much better that it outweighs the cost of adopting a new language (which is steep).

It's why we are still on QWERTY despite DVORAK being a tiny bit better. For most typists it doesn't matter, they will never make up the time spent learning DVORAK with the time saved typing DVORAK.

The same with programming languages. Most new programming languages aren't that much better than the old ones. Maybe they fix one or two problems, but at the same time, they're less mature and critically, who knows if they will be around in 20-30 years. C will be around in 30 years, C++ too, PHP will, Java certainly. Rust, honestly, I dunno. Could go either way, and it's not because people aren't adopting it fast enough that I'm hesitating. When Rust has been around longer, I will be more confident that it will stay around, and then I may consider using it.

[ncmncm]

Absolutely, being better on one or more axes is only table stakes. An essential prerequisite to the miracle, besides, is wide adoption, because without, why would anybody put in the time to get proficient? You have only a short time to get there. With too-slow adoption, you miss the window.

But we are already off in the weeds. Why argue that slow adoption might suffice, instead of doing everything needed to drive up adoption? Would it be so bad to do a thing that might turn out not to have been obviously necessary? Hype only goes so far, and has gone there already.

To me the clearest indication that any language will fizzle is when its boosters insist it doesn't need to do anything not to.