Tectonic is a fabulous new implementation of TeX that doesn't require a large distribution, doesn't write intermediate files, and automatically loops TeX and BibTeX!
Bootstrapping a full GCC toolchain from an extremely minimal hex editor has an astounding number of steps: https://github.com/fosslinux/live-bootstrap/blob/master/parts.rst
I didn't realise just how many tools are self-hosting. Not just GCC, but also flex, bison, automake and even perl!
What languages have changed the most since their creation?
JS? IIFEs and prototypes to modules and classes.
C++? Plain pointers to smart pointers.
There must be more dramatic examples.
TIL that &mut [T] in Rust means that you can modify the items in a slice, but you can't change its size. It's surprisingly handy: I'd just been using &mut Vec<T> everywhere previously.
The number of tools a programming language is expected to provide is growing over time. This in-depth article describes what Rust provides: you can't just ship a compiler these days.
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