• Brad King's avatar
    Add boolean generator expressions · ebf05abd
    Brad King authored
    Add generator expressions that combine and use boolean test results:
    
     $<0:...>         = empty string (ignores "...")
     $<1:...>         = content of "..."
     $<AND:?[,?]...>  = '1' if all '?' are '1', else '0'
     $<OR:?[,?]...>   = '0' if all '?' are '0', else '1'
     $<NOT:?>         = '0' if '?' is '1', else '1'
    
    These will be useful to evaluate (future) boolean query expressions and
    condition content on the results.  Include tests and documentation.
    ebf05abd