add docstring for add_artifact!

docs/src/index.md

@@ -5,6 +5,7 @@ CurrentModule = ArtifactUtils
 # ArtifactUtils
 
 ```@index
+add_artifact!
 ```
 
 ```@autodocs

src/ArtifactUtils.jl

@@ -14,6 +14,33 @@ function sha256sum(tarball_path)
 end
 
 
+"""
+    function add_artifact!(
+        artifacts_toml::String, name::String, tarball_url::String;
+        clear=true,
+        platform::Union{Platform,Nothing} = nothing,
+        download_info::Union{Vector{Tuple},Nothing} = nothing,
+        lazy::Bool = false,
+        force::Bool = false
+    )
+
+Downloads tarball from `tarball_url`, extracts it and adds it as an artifact with name
+`name` to the file `artifacts_toml`. If `clear` is true, the artifact itself is deleted
+afterwards. The rest of the keyword arguments are passed to `Pkg.Artifacts.bind_artifact!`.
+
+From [its docstring](https://julialang.github.io/Pkg.jl/dev/api/#Pkg.Artifacts.bind_artifact!):
+
+> If `platform` is not `nothing`, this artifact is marked as platform-specific, and will be
+> a multi-mapping.  It is valid to bind multiple artifacts with the same name, but
+> different `platform`s and `hash`'es within the same `artifacts_toml`.  If `force` is set
+> to `true`, this will overwrite a pre-existant mapping, otherwise an error is raised.
+>
+> `download_info` is an optional vector that contains tuples of URLs and a hash.  These
+> URLs will be listed as possible locations where this artifact can be obtained.  If `lazy`
+> is set to `true`, even if download information is available, this artifact will not be
+> downloaded until it is accessed via the `artifact"name"` syntax, or
+> `ensure_artifact_installed()` is called upon it.
+"""
 function add_artifact!(
     artifacts_toml::String,
     name::String,