There is a famous paper on the perils of scripting in the csh. It is unfortunate that Bill Joy was not able to write a formal grammar or parser for his language. It was certainly a missed opportunity, and tcsh cannot fix the design.

That being said, csh advocates definitely influenced everything in the Bourne/POSIX family.

It's a classic Usenet post that deserves linking at every opportunity!

https://harmful.cat-v.org/software/csh