Distribution.Client.ProjectConfig.Types

This type corresponds directly to what can be written in the cabal.project file. Other sources of configuration can also be injected into this type, such as the user-wide config file and the command line of cabal configure or cabal build.

Since it corresponds to the external project file it is an instance of Monoid and all the fields can be empty. This also means there has to be a step where we resolve configuration. At a minimum resolving means applying defaults but it can also mean merging information from multiple sources. For example for package-specific configuration the project file can specify configuration that applies to all local packages, and then additional configuration for a specific package.

Future directions: multiple profiles, conditionals. If we add these features then the gap between configuration as written in the config file and resolved settings we actually use will become even bigger.

The project configuration is configuration that is parsed but parse configuration may import more configuration. Holds the unparsed contents of an imported file contributing to the project config.

That part of the project configuration that only affects how we build and not the value of the things we build. This means this information does not need to be tracked for changes since it does not affect the outcome.

Project configuration that is shared between all packages in the project. In particular this includes configuration that affects the solver.

Specifies the provenance of project configuration, whether defaults were used or if the configuration was read from an explicit file path.

Project configuration that is specific to each package, that is where we can in principle have different values for different packages in the same project.

Resolved configuration for the solver. The idea is that this is easier to use than the raw configuration because in the raw configuration everything is optional (monoidial). In the BuildTimeSettings every field is filled in, if only with the defaults.

Use resolveSolverSettings to make one from the project config (by applying defaults etc).

Resolved configuration for things that affect how we build and not the value of the things we build. The idea is that this is easier to use than the raw configuration because in the raw configuration everything is optional (monoidial). In the BuildTimeSettings every field is filled in, if only with the defaults.

Use resolveBuildTimeSettings to make one from the project config (by applying defaults etc).

How to control parallelism, e.g. a fixed number of jobs or by using a system semaphore.

Determine if the parallelism strategy enables parallel builds.

Used by Cabal to indicate that we want to use this specific semaphore (created by cabal-install)

Newtype wrapper for Map that provides a Monoid instance that takes the last value rather than the first value for overlapping keys.

Newtype wrapper for Map that provides a Monoid instance that mappends values of overlapping keys rather than taking the first.