I am trying to create a tag library for PagePlanets MGI tags. One of the
problems that I am having is that there are some tags that allow multiple
repeated entries of the same attribute. For example in the mgiDate tag you can
have multiple format attributes. So for example to return the date as something
like YYMMDD you would use:
<mgiData format="ShortYear" format="PaddedNumericMonth" format="PaddedDay">

The problem is that D8 doesn't like the multiple format entries. Is there any
way in the vtm file to allow for multiple same entries?

Also, in a similar vein, there are valid combinations of attributes that can
get quite complex. For example there is an mgiString tag that is of the
following form: <mgiString mode="mode" ....optional attrib> depending on the
mode the valid attributes are different. Is there a way to say that for
mode="trim" the following parameters are valid: chacter, quoteResult,
while for mode="split" the optional parameters are delimeter and index?