document equivalent built-in LSP actions

[edwintorok]

Some actions provided by the plug-in are duplicate with what is already available via the built-in LSP.
That doesn't mean they are not useful, sometimes the code actions are hard to discover (you only know what is available if you try it in various different situations)

E.g.:

• :InferIntf is equivalent to gra (code action), and then selecting 1 Insert inferred interface
• :AlternateFile is equivalent to gra, and then selecting 2 Create <filename.mli> . Except the position is not predictable with code actions (sometimes it might be 3, e.g. if Destruct is available), or 2 Open <filename.mli> (same for .ml when you are in the mli)

[edwintorok]

Also maybe documenting closely related LSP actions might be useful.
E.g. the various lookup actions defined by this plugin have equivalents when you want to use the identifier under the cursor instead:

• :FindIdentifierDefinition <id> is equivalent to gd cursor is on , or 'ctrl-]` when the LSP integration is enabled (it sets tagfunc)
• :FindIdentifierDeclaration <id> is equivalent to :lua vim.lsp.buf.declaration() (no keybinding by default AFAICT)
• :DocumentIdentifier <id> is equivalent to K when cursor is on <id>

[Lucccyo]

Thanks for the comparison with the existing LSP.
You are right, some actions provided by this plugin overlap with the built-in LSP features.
This duplication is intentional. The goal of the plugin is to make these features more accessible without requiring users to search through the code action list. I feel that, for example, :OCamlSwitchIntfImpl is a valuable feature, and having a built-in command for that is a plus.
That said, documenting the equivalent built-in LSP code actions as you suggested could help users understand how things are mapped together, which is a good idea.