MariaDB (5.2.0+) supports virtual columns and the syntax is 

<type>  [GENERATED ALWAYS]  AS   ( <expression> ) [VIRTUAL | PERSISTENT]  [UNIQUE] [UNIQUE KEY] [COMMENT <text>]

While implementing [1], to add parser support for virtual columns, I tried to model this syntax using $FIELD_OPTIONS [2]. Even though I am able to retrieve the expression this way, all the brackets and spaces of the expression are gone. As I understand, this due to the tokenization. 

Do you have any suggestion for an alternative approach?

[1] https://sourceforge.net/p/phpmyadmin/feature-requests/1517/

[2] https://github.com/madhuracj/phpmyadmin/commit/b287aae9d56c4ae15d850b47a5f76d49f4f155ba
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