Function call basic

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#cmd(value basic, key=value, :flag, {markdown}){body}
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(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")
        )
    )
)