Can Rust retarget GTK or QT ? Actually, the important question is whether it is meant to.
Will it ever be intended to replace application languages like Vala, Mono (used to write Tomboy, Banshee, etc.) or will it be restricted to system level stuff.
Yes, Rust is intended to play nicely with GTK and Qt. For one, browser engines need to interface to the platform-native toolkits.
Scripting support would be cool. To me, Rust isn't necessarily the best language to write small one-off scripts in; I personally prefer dynamically typed languages (or whole-program type-inferred languages) for that. But if you want to write scripts in Rust, I'd certainly review any pull requests to make it easier :)
I'm more interested in an alternative to write desktop apps in, rather than small one off scripts.
I'm interested in this from a vision point of view. What are going to be your first "written-using-Rust" apps ? Firefox is gargantuan, so it cant be your first. Ergo, the question about platform toolkit compatibility. If you build that one first, you will start spawning an ecosystem almost instantly... if you want.
Mono, Vala, etc. have nice apps that people love. I am wondering on how can you bridge the gap between javascript/Qtscript and Rust to make it easier to build apps in.
>What are going to be your first "written-using-Rust" apps ?
Rust compiler is written in rust, so that would be the first "written-using-Rust" app. Additionally afaik the work on rust-based web-browser (engine) has began, so that would be second (major) project for rust.
Will it ever be intended to replace application languages like Vala, Mono (used to write Tomboy, Banshee, etc.) or will it be restricted to system level stuff.
If yes, will there ever be scripting support (like Ocaml https://ocaml.janestreet.com/?q=node/80)
edit: Rust has a nice decentralized package manager as well called Cargo https://github.com/mozilla/rust/wiki/Doc-using-cargo-to-mana... ) Pretty nice.