[nonsince]

I don't know about the others (reportedly Cling for C++ is good) but the Rust repl doesn't work properly and is basically just a frontend for incrementally writing a Rust file.

[steveklabnik]

Not only that but it’s about a year out of date at this point.

I’m hoping someone eventually makes a new one, possibly based on MIRI.

[sam0x17]

This is also the current state of the crystal repl shard