stack.md

Stack

Project Discovery

Find all directories with a stack.yaml file. When one is found, skip all subdirectories.

Analysis

From the project root, we run stack ls dependencies json, which outputs JSON in the following format.

Extra data removed for brevity

[
    {
        "location": {
            "type": "hackage"
        },
        "name": "remote",
        "version": "remote-ver",
        "dependencies": [
            "deep"
        ]
    },
    {
        "location": {
            "type": "project package"
        },
        "name": "local",
        "version": "local-ver",
        "dependencies": [
            "remote",
            "builtin"
        ]
    },
    {
        "location": {
            "type": "hackage"
        },
        "name": "deep",
        "version": "deep-ver",
        "dependencies": []
    },
    {
        "name": "builtin",
        "version": "builtin-ver"
    }
]

Analysis has two notable parts: matching name fields from the strings in dependencies, and noting the package's location.type. A package with a missing location.type refers to a builtin, ghc-provided package, and a present field takes one of two forms: remote and local, which have different sets of string associated with them. Local packages are references to the current project, while remote references are pointers to package or source repositories.