Method optimize

basex-core/src/main/java/org/basex/query/expr/If.java:67–84

(final CompileContext cc)

  }

  @Override
  public Expr optimize(final CompileContext cc) throws QueryException {
    if(EMPTY.is(cond)) {
      // if(empty(A)) then B else C → if(exists(A)) then C else B
      cond = cc.function(EXISTS, cond.info(info), cond.arg(0));
      swap();
      cc.info(QueryText.OPTSWAP_X, this);
    } else if(NOT.is(cond)) {
      // if(not(A)) then B else C → if(A) then C else B
      cond = cond.arg(0);
      swap();
      cc.info(QueryText.OPTSWAP_X, this);
    }
    // if(exists($nodes)) → if($nodes)
    cond = cond.simplifyFor(Simplify.EBV, cc);

    return cc.replaceWith(this, opt(cc));
  }

  /**
   * Optimizes the expression.