pecan

Type system

Factory type

Every occurrence of pecan.Co.co(...) internally declares a new class that is a factory for instances of the created coroutine. This class cannot implement any particular interface, because every coroutine declaration may have a different number of arguments. Informally, the interface is:

interface CoFactory<T> { // T is the coroutine instance type
  function run(args...):T;
  function runSuspended(args...):T;
}

Instance type

Every occurrence of pecan.Co.co(...) also declares an instance type. An instance represents a called coroutine and it is responsible for storing its internal state.

Every coroutine instance type implements the interface pecan.ICo<TIn, TOut, TRet>, where:

• TIn is the input type (the type returned by accept() calls) or Void,
• TOut is the output type (the argument provided to yield(...) calls) or Void, and
• TRet is the return type.

A Void return type is always replaced by pecan.Void, to avoid issues with Void cannot be used as a value errors in Haxe.