reachable

可达成的, 可获得的中释adj

1 It then traverses the chain of references until all (directly or indirectly) reachable objects from the root set are marked..跟踪然后遍历引用链直至标记完根集中所有（直接或间接）可获得的对象。

2 To make life easier (and it is good practice anyway), we make sure that all data is reachable from the root of a single tree of data structures in memory..为了让生活更容易（它总是一个很好的实践），我们必须确保所有的数据从单一数据结构书的根上是可获得的。