Comment by gdwatson
15 hours ago
Historically, different Unixes varied a lot more than they do today. Say you want your program to use the C library function foo on platforms where it’s available and the function bar where it isn’t: You can write both versions and choose between them based on a C preprocessor macro, and the program will use the best option available for the platform where it was compiled.
But now the user has to set the preprocessor macro appropriately when he builds your program. Nobody wants to give the user a pop quiz on the intricacies of his C library every time he goes to install new software. So instead the developer writes a shell script that tries to compile a trivial program that uses function foo. If the script succeeds, it defines the preprocessor macro FOO_AVAILABLE, and the program will use foo; if it fails, it doesn’t define that macro, and the program will fall back to bar.
That shell script grew into configure. A configure script for an old and widely ported piece of software can check for a lot of platform features.
I'm not saying we should send everyone a docker container with a full copy of ubuntu, electron and foo.js whether they have foo in their c library or not, but maybe there is a middle ground?
I think this is a gigantic point in favor of interpreted languages.
JS and Python wouldn't be what they are today if you had to `./configure` every website you want to visit, lmao.
> JS and Python wouldn't be what they are today if you had to `./configure` every website you want to visit, lmao.
You just gave me a flashback to the IE6 days. Yes, that's precisely what we did. On every page load.
It's called "feature detection", and was the recommended way of doing things (the bad alternative was user agent sniffing, in which you read the user agent string to guess the browser, and then assumed that browser X always had feature Y; the worst alternative was to simply require browser X).