[ Allow predicate question marks ]
[ Allow predicate question marks ]

Like in ruby, question marks are allowed at the end of literals.  They become capital Qs, which is otherwise impossible to create.  first? becomes firstQ in javascript.  I'm not sure if this should be firstP for predicate, but Q seems more immediately understandable.
jbr/sibilant,jbr/sibilant,cesarmarinhorj/sibilant,cesarmarinhorj/sibilant