Of other code search sites

As an addendum to my praise of GitHub’s advanced search, I’ve come across additional sites where code can be searched. Namely:

• grep.app: https://grep.app/
• Sourcegraph: https://sourcegraph.com/search
• Heline: https://heline.dev/

The latter seems to be somewhat lacking in its results compared to the others, but could still be helpful in a pinch!