JetFile: PredicateExpression.jet
  NAMESPACE
    FUN
      PsiElement(fun)('fun')
      PsiWhiteSpace(' ')
      PsiElement(IDENTIFIER)('foo')
      VALUE_PARAMETER_LIST
        PsiElement(LPAR)('(')
        PsiElement(RPAR)(')')
      PsiWhiteSpace(' ')
      BLOCK
        PsiElement(LBRACE)('{')
        PsiWhiteSpace('\n  ')
        DOT_QUALIFIED_EXPRESSION
          PREDICATE_EXPRESSION
            REFERENCE_EXPRESSION
              PsiElement(IDENTIFIER)('a')
            PsiElement(QUEST)('?')
            REFERENCE_EXPRESSION
              PsiElement(IDENTIFIER)('f')
          PsiElement(DOT)('.')
          REFERENCE_EXPRESSION
            PsiElement(IDENTIFIER)('foo')
        PsiWhiteSpace('\n')
        PsiElement(RBRACE)('}')