define new keyword

Question

I would like to add new keywords to have plantuml parse code from a fixed dsl:

I do not find an external  file where i can extend the grammar and usage of define do not match requirement as it do not support parameters without ().

i would like a new define like this:

!definekeyword  group ? : class ? <<(g,blue)>>

!definekeyword  info ?1 { ?2  }  : note ?1  ?2 end note

 

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