Type declarations

`val mk : ?⁠loc:loc ‑> ?⁠attrs:attrs ‑> ?⁠docs:Ppxlib_ast.Docstrings.docs ‑> ?⁠text:Ppxlib_ast.Docstrings.text ‑> ?⁠params:(Ppxlib_ast__.Import.Parsetree.core_type * Ppxlib_ast__.Import.Asttypes.variance) list ‑> ?⁠cstrs:(Ppxlib_ast__.Import.Parsetree.core_type * Ppxlib_ast__.Import.Parsetree.core_type * loc) list ‑> ?⁠kind:Ppxlib_ast__.Import.Parsetree.type_kind ‑> ?⁠priv:Ppxlib_ast__.Import.Asttypes.private_flag ‑> ?⁠manifest:Ppxlib_ast__.Import.Parsetree.core_type ‑> str ‑> Ppxlib_ast__.Import.Parsetree.type_declaration`
`val constructor : ?⁠loc:loc ‑> ?⁠attrs:attrs ‑> ?⁠info:Ppxlib_ast.Docstrings.info ‑> ?⁠args:Ppxlib_ast__.Import.Parsetree.constructor_arguments ‑> ?⁠res:Ppxlib_ast__.Import.Parsetree.core_type ‑> str ‑> Ppxlib_ast__.Import.Parsetree.constructor_declaration`
`val field : ?⁠loc:loc ‑> ?⁠attrs:attrs ‑> ?⁠info:Ppxlib_ast.Docstrings.info ‑> ?⁠mut:Ppxlib_ast__.Import.Asttypes.mutable_flag ‑> str ‑> Ppxlib_ast__.Import.Parsetree.core_type ‑> Ppxlib_ast__.Import.Parsetree.label_declaration`