Get started with lal easier

[bencord0]

Remove the configs/ and remove the need to provide
a defaults file on first startup.

From a fresh checkout, can

$ cargo build
$ cargo run -- configure
$ cargo run -- build

This is now because the manifest file can contain
the environment definitions, and lal will fallback
to the user-wide environment definitions only if
not found (to preserve behaviour).

[clux]

comments and a question

[clux]

these are equivalent, right?

[bencord0]

Vec::new can be given in places that expect a FnOnce() -> Vec, and is a little bit easier on the compiler as it doesn't need to evaluate the macro.

I think what I actually want to do is this:

let xs: Vec<&str> = a.values_of("parameters")
    .map_or_else(Vec::new, |params| params.collect());

[bencord0]

environments at the manifest level?

Yeah, I want to decouple the repository's definition of the environment from the user's definition of the environment.

My intention is to not require the build environment be configured locally at all, and can be upgraded with the repository. This also helps keep the build environment needed for the code in sync through the code itself.

That said, I think that having locally defined the version of the environments is still useful as an override (because users could always maintain a local patch to the manifest's environment); the question then becomes one about precedence - should ~/.lal/config:environments override .lal/manifest.json:environments, or should it be the other way around.

---

On having the manifests across multiple repositories;

I think I'm okay with this sprawl. There are tools like https://github.com/Clever/microplane which have solve this problem for me in recent years.

abi compatibility between targets that are built in the same env

This is a really compelling argument for having the local config override the repo manifest's definition of the environment. I'll swap them around so that
a) existing users who have their local environment definitions setup continue to build in a consistent ABI
b) new users who don't have their environment defaults can build repositories that do have their own definitions.

• Swap precedence of environments key. local overrides repo.
• Add a tests for repo manifests without environments, builds should still pass if the environment is defined in ~/.lal/config.