Function tryUnpackNoNameArg

Returns
    | "<>"
    | RArgument<OtherInfo>
    | RExpressionList<OtherInfo>
    | RFunctionDefinition<OtherInfo>
    | RNamedFunctionCall<OtherInfo>
    | RUnnamedFunctionCall<OtherInfo>
    | RParameter<OtherInfo>
    | RComment<OtherInfo>
    | RLineDirective<OtherInfo>
    | RForLoop<OtherInfo>
    | RRepeatLoop<OtherInfo>
    | RWhileLoop<OtherInfo>
    | RIfThenElse<OtherInfo>
    | RNamedAccess<OtherInfo>
    | RIndexAccess<OtherInfo>
    | RUnaryOp<OtherInfo>
    | RBinaryOp<OtherInfo>
    | RSymbol<OtherInfo, Identifier>
    | RNumber<OtherInfo>
    | RString<OtherInfo>
    | RLogical<OtherInfo>
    | RBreak<OtherInfo>
    | RNext<OtherInfo>
    | RPipe<OtherInfo>