What is a Path Dependent Type?
A path dependent type is a type that is dependent on the path in which it is accessed. The type of a variable or object is determined not by its own structure or characteristics, but rather by the path in which it is accessed.
Example 1:
Scala
class Bar { type T } // Now, if we define two instances of Bar, // bar1 and bar2, we can create a type T1 and a // type T2, which are both dependent on // the path in which they are accessed: val bar1 = new Bar val bar2 = new Bar val t1: bar1.T = ??? val t2: bar2.T = ??? |
Explanation:
Here, t1 is of type bar1.T and t2 is of type bar2.T. The type of t1 and t2 are determined not by the structure of the instances of Bar, but rather by the path in which they are accessed.
Scala Path Dependent Type
Scala Path Dependent Types (PDTs) are an advanced feature of the Scala language that allows users to create types that are dependent on the path in which they are accessed. The type of a variable or object is not determined by its own structure or characteristics, but rather by the path in which it is accessed. This allows for a more flexible and powerful type system, allowing for more complex and expressive types.