Reflection

Reflection makes us call a specified function or set by a name string.

Function reflection

@foo ()
{
  sys = Import('sys');
  sys.print('foo');
}
a = 'foo';
a();

As we can see, variable a is a string but a function, but its value is a function name. The last statement will output foo on terminal, because function foo is called.

Let’s see a more complex example:

@foo ()
{
  sys = Import('sys');
  sys.print('foo');
}
a = 'foo';
b = 'a';
b();

This example will output foo on terminal either.

Set reflection

sys = Import('sys');

human {
  name;
  age;
}
s = 'human';
Tom = $s;
sys.print(Tom);

s is a string variable, and its value is a set name.

The output is Object. Which means, Tom = $s; is working. Tom is an object of set human.

Method reflection

If function has reflection, so does method.

Let’s see a comprehensive example:

human {
  action;
  @run ()
  {
    sys = Import('sys');
    sys.print('running');
  }
}
s = 'human';
Tom = $s;

Tom.action = 'run';
Tom.action();

The result of this program is:

running

The first part is a set reflection to instantiate an human object. And set object’s action to be a string which is the method name run. And then call object method via object property.

Note: The code shown below is not working.

s = 'run';
Tom.s();