如何在 Chapel 中使用 `writeThis()` 结构

Question

我在 Chapel 中有一个 class，我想让它控制自己的打印语句。例如

class Noob {
  var name: string,  experience:int;
  // constructor
}

之后，我想做一些类似的事情

me = new Noob('brian', 0)
writeln(me)

> Hi, my name is Brian and I have 0 years experience

看起来 this 应该有所帮助，但我无法完全使用 readThis() 方法。

Answer 1

您需要一个 writeThis(f) 方法来覆盖对象的默认 writeln 行为：

class Noob {
  var name: string,  experience:int;

  proc writeThis(f) {
    f.writef('Hi, my name is %s and I have %t years experience',
             this.name, this.experience);
  }
}

var noob = new Noob('ben', 2);

writeln(noob);

您还可以在 readWriteThis(f) 方法中使用 <~> 运算符来处理对象的读写：

class Noob {
  var name: string,  experience:int;

  proc readWriteThis(f) {
    f <~> 'Hi, my name is %s and I have %t years experience'.format(this.name, this.experience);
  }
}

如何在 Chapel 中使用 `writeThis()` 结构

How to use the `writeThis()` construct in Chapel

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