How to specify custom path to dependencies?

[Andrew]

I wish cargo-script were able to load dependencies from the regular Cargo.toml file, as that system is able to handle more complicated dependency configurations. For example, Cargo.toml can specify custom paths for dependencies installed locally rather than from crates.io. This speeds up my work, relieving the need to continually publish half-ass packages to crates.io during prototyping.

I would rather have cargo-script obtain dependencies via the normal Cargo.toml system, but if that is right out, then it would be nice to have this little custom path feature for now.