@Override
    public boolean equals(Object other) {
        if (this==other) return true;
        if ( ! (other instanceof Value)) return false;
        if ( ! ((Value) other).hasDouble()) return false;
        return this.value == ((Value) other).asBoolean();
    }
Create a boolean value which is frozen at the outset.
searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/BooleanValue.java