Speaking as someone who was the "re-implementee" in some cases (i.e. our mixed C/C++ regex library Hyperscan has had some ideas borrowed for your regex library in Rust) I'd say things aren't 100% simple here.
I think there is a strong tendency of people programming in new languages to be overly convinced of the elegance and superiority of their new language as a result of (a) getting to rewrite software without the burden of those fussy, irritating existing users and (b) getting to 'rebuild' software without the rather exhausting process of feeling your way to an algorithm or system that never existed before.
There's absolutely nothing wrong with either of these things, but sometimes I think people working in hip new languages tend to mistake the elegance and superiority of their new language for the advantages conferred by a "rework". I bet I could build a pretty elegant regular expression system in C/C++ if I got to start from scratch, too!
This isn't a statement about one language being better than another, and I'm aware of how vexed a problem it is to compare new languages with old. If you built a pile of nonesuch systems in your new language people would complain that they can't compare these systems with stuff that they're familiar with. :-)
I'd just call for a bit of caution in assessing new languages being pressed into service for old, familiar tasks.
I think there is a strong tendency of people programming in new languages to be overly convinced of the elegance and superiority of their new language as a result of (a) getting to rewrite software without the burden of those fussy, irritating existing users and (b) getting to 'rebuild' software without the rather exhausting process of feeling your way to an algorithm or system that never existed before.
There's absolutely nothing wrong with either of these things, but sometimes I think people working in hip new languages tend to mistake the elegance and superiority of their new language for the advantages conferred by a "rework". I bet I could build a pretty elegant regular expression system in C/C++ if I got to start from scratch, too!
This isn't a statement about one language being better than another, and I'm aware of how vexed a problem it is to compare new languages with old. If you built a pile of nonesuch systems in your new language people would complain that they can't compare these systems with stuff that they're familiar with. :-)
I'd just call for a bit of caution in assessing new languages being pressed into service for old, familiar tasks.