Interface infrastructure for a continuation based runtime

In a computing environment, a computer readable storage media having stored thereon computer executable instructions for implementing a framework for enabling the creation and/or execution of continuation-based declarative applications, the computer readable medium comprising the following:

• a first plurality of APIs, each of which being for writing continuation based runtimes, wherein each of the first plurality of APIs are included in a first common namespace for an activity model of a continuation-based runtime, wherein each of the first plurality of continuation based runtime APIs are represented with a first common namespace prefix for logical grouping of the plurality of continuation-based runtime APIs, the first plurality of APIs comprising:
• a first API class that represents continuation-based behavior, wherein instances of the class include imperative code in their bodies that is executed by a processor to perform functions;
• and
• a second API class that is used for declaratively composing continuation-based behaviors of the first class into new types by declaring one or more instances of the first API class.
• a second plurality of APIs, wherein each of the second plurality of APIs are included in a second common namespace having common characteristics that re not present in all of the first plurality of APIs.

In a computing environment, a computer readable storage media having stored thereon computer executable instructions for implementing a framework for enabling the creation and/or execution of continuation-based declarative applications, the computer readable medium comprising the following:

• a first plurality of APIs organized in a first common namespace and that are represented with a first common namespace prefix for logical grouping, wherein first plurality of APIs are for an activity model of a continuation-based runtime;
• a second plurality of APIs organized in a second common namespace and that are represented with a second common namespace prefix for logical grouping, wherein the second plurality of APIs are used to host, execute, and manage instances of continuation-based, declarative programs;
• a third plurality of APIs organized in a third common namespace and that are represented with a third common namespace prefix for logical grouping, wherein the third plurality of APIs are used to implement a base layer of activities that add functionality to the continuation-based runtime and that are used to add concrete behaviors that build on top of a core activity model;
• a fourth plurality of APIs organized in a fourth common namespace and that are represented with a fourth common namespace prefix for logical grouping, wherein the fourth plurality of APIs are used for providing and executing build constraints and policy constraints, wherein build constraints validate that a given workflow does not violate any runtime or activity assumptions which would most likely cause runtime exceptions and wherein policy constraints warn of potential issues including one or more of best practice violations, design guideline violations, or company policy violations;
• a fifth plurality of APIs organized in a fifth common namespace and that are represented with a fifth common namespace prefix for logical grouping, wherein the fifth plurality of APIs are used for defining and consuming tracking events;
• and
• a sixth plurality of APIs organized in a sixth common namespace and that are represented with a sixth common namespace prefix for logical grouping, wherein the sixth plurality of APIs are used for modeling communication with other systems by sending and receiving messages in and out of a workflow, and for representing a continuation-based program as a service.