Function call basic
=======
#cmd(value basic, key=value, :flag, {markdown}){body}
=======
(doc
(command
(command_name (ident: "cmd"))
(parameters
(param (basic_val: "value basic"))
(param (key: "key") (basic_val: "value"))
(param (flag: "flag"))
(param (md_val (string: "markdown")))
)
(body_def
(body: "body")
)
)
)