[stringtemplate-interest] Spaces around template attributes

[Steve Ebersole]

I am trying to deal with extra spaces in my stringtemplate output when
attribute values used within the template are null/empty.  I figure this
has to be a pretty common requirement, so I thought I'd ask here how to
accomplish this.

For example, I have a template like:
sortSpecification(sortKey,collationSpecification,orderingSpecification) ::= <<
<sortKey> <collationSpecification> <orderingSpecification>
>>

Only 'sortKey' is required in the corresponding (SQL-based) grammar.  So
if you consider a call to this template with sortKey="a",
collationSpecification=null, orderingSpecification="asc" the output here
ends up being "a  asc" (notice the 2 spaces between 'a' and 'asc').  

So how to handle this such that the extra spaces are omitted?  I
understand I *can* do something like:
sortSpecification(sortKey,collationSpecification,orderingSpecification) ::= <<
<sortKey><if(collationSpecification)>
<collationSpecification><endif><if(orderingSpecification)>
<orderingSpecification><endif>
>>

But personally I think that starts detracting from the readability of
the expression.

-- 
Steve Ebersole <steve at hibernate.org>
Hibernate.org