func dnfComplexity(expr expression.Expression, max int) int {
comp := 0
switch expr := expr.(type) {
case *expression.Or:
comp = len(expr.Operands())
}
if comp < max {
children := expr.Children()
for _, child := range children {
childComp := dnfComplexity(child, max-comp)
comp += childComp
if comp >= max {
break
}
}
}
return comp
}
