小编min*_*910的帖子

我正在使用基于示例Clang ASTFrontendActions 示例的LibTooling 为 clang 4.0 编写工具。给定当前语句 stmt，我想在 AST 中获取它的直接父级。因此，我尝试使用以下代码转储 stmt 的所有父级（用于测试目的）：

bool VisitStmt(Stmt *s) {
    cout <<"Trying to get parents \n";
    const Stmt  currentStmt = *s;
    const auto& parents  = Context->getParents(currentStmt);
    auto it = Context->getParents(currentStmt).begin();
    if(it == Context->getParents(currentStmt).end())
        cout<< "parents not found\n";
    cout<<"parents size "<< parents.size() <<": \n";
    if (!parents.empty()){
        for (int i = 0; i< parents.size(); i++ ){
            cout<<"parent at "<< i <<": \n";
            const Stmt* parentStmt =  parents[i].get<Stmt>();
            parentStmt->dump();
        }

    }
}

Context在ASTContext …

有没有一种方法可以检查scala中foreach循环中的条件。这个例子是我要遍历一个整数数组并对正数做一些任意的数学运算。

val arr = Array(-1,2,3,0,-7,4) //The array

//What I want to do but doesn't work

arr.foreach{if(/*This condition is true*/)
              {/*Do some math and print the answer*/}}

//Expected answer for division by six is 0.333333333 \n 0.5 \n 0.666666667
//Which is 2/6, 3/6 and 4/6 respectively as they appear in the array

我知道如何使用普通的for循环和if语句来执行此操作，但是我想使用它，因为我想摆脱Java。

谢谢