Module org.kink_lang.kink
Package org.kink_lang.kink.hostfun

Interface HostContext

All Known Subinterfaces:
CallContext
public interface HostContext
Context of an action of a host fun.

The context is valid during invocation of the lambda of HostFunBuilder.action(ThrowingFunction1) or CallFlowToOn.on(HostFunReaction).

See org.kink_lang.kink.hostfun for usage.

  • Method Details

    • traces

      List<TraceVal> traces()
      Returns the traces to the current execution stack.

      The traces are ordered from the bottom to the top, unlike stack trace in Java.

      Returns:
      the traces to the current execution stack.

    • raise

      HostResult raise(String msg)
      Returns a HostResult to raise an exception.
      Parameters:
      msg - the message of the exception.
      Returns:
      a HostResult to raise an exception.

    • raise

      HostResult raise(Throwable throwable)
      Returns a HostResult to raise an exception made from the Java throwable.
      Parameters:
      throwable - the throwable of which a kink exception is made.
      Returns:
      a HostResult to raise an exception.

    • call

      CallFlowToRecv call(FunVal fun)
      Returns a call flow to call the fun, with nada as the recv and no args.

      Example:

        FunVal curry2 = vm.fun.make("curry2($fun)").take(1).action(c -> {
      Val funArg = c.getArg(0);
      if (! (funArg instanceof FunVal)) {
          return c.call(vm.graph.raiseFormat("curry2($fun): required a fun, but got {}",
              vm.graph.repr(funArg)));
      }
      FunVal fun = (FunVal) funArg;
      FunVal curried = vm.fun.make().take(1).action(cc -> {
          Val a0 = cc.getArg(0);
          return vm.fun.make().take(1).action(c3 -> {
              Val a1 = c3.getArg(0);
              return c3.call(fun).args(a0, a1);
          });
      });
  });
      Parameters:
      fun - the fun.
      Returns:
      a call flow to call the fun.

    • call

      CallFlowToRecv call(Val ownerRecv, int symHandle)
      Returns a call flow to call a method of ownerRecv with no args.

      The ownerRecv is also set as the recv of the call.

      Example:

        int opAddHandle = vm.sym.getHandle("op_add");
  FunVal increment = vm.fun.make().take(1).action(c -> {
      Val n = c.getArg(0);
      // call “n + 1”
      return c.call(n, opAddHandle).args(vm.num.of(1));
  });

      If the specified var is empty, or the target of the var is not a fun, call() method returns a call flow which raises an exception.

      Parameters:
      ownerRecv - the owner and the recv of the method.
      symHandle - the sym handle of the method.
      Returns:
      a call flow with the fun.

    • call

      CallFlowToArgs call(String modName, int symHandle)
      Returns a call flow to call a fun in the specified mod with no args.

      nada is set as the recv of the call.

      Example:

        int exit = vm.sym.getHandle("exit");
  FunVal abort = vm.fun.make().take(0).action(
      c -> c.call("kink/PROCESS", exit).args(vm.num.of(1)));

      If the specified fun is empty, or the target of the var is not a fun, call() method returns a call flow which raises an exception.

      Parameters:
      modName - the name of the mod containing the fun.
      symHandle - the sym handle of the fun.
      Returns:
      a call flow.

    • call

      CallFlowToOn call(GraphNode graph)
      Returns a call flow to evaluate the graph.

      Example:

        FunVal abs = vm.fun.make().take(0).action(c -> {
      Val num = c.getArg(0);
      if (! (num instanceof NumVal)) {
          return c.call(vm.graph.raiseFormat("unknown val {}", vm.graph.repr(num)));
      }
      BigDecimal dec = ((NumVal) num).getBigDecimal();
      return vm.num.of(dec.abs());
  });
      Parameters:
      graph - the graph to evaluate.
      Returns:
      a call flow to evaluate the graph.