Dataflow processing with events

• US 6,272,672 B1
• Filed: 09/06/1995
• Issued: 08/07/2001
• Est. Priority Date: 09/06/1995
• Status: Expired due to Term

• Current Assignee: Melvin E. Conway
• Original Assignee: Melvin E. Conway
• Inventors: Conway, Melvin E.
• Primary Examiner(s): Hafiz, Tariq R.
• Assistant Examiner(s): INGBERG, TODD D
• Application Number:
  US08/524,170
• Time in Patent Office: 2,162 Days
• Field of Search: 395/701, 395/702, 395/703, 395/704, 395/705, 395/706, 395/707, 395/708, 395/709, 395/710, 395/712, 345/326, 345/333-335, 717/1
• US Class Current: 717/107
• CPC Class Codes: G06F 9/452 Remote windowing, e.g. X-Window System, desktop virtualisation protocols for virtual reality H04L67/131

Abstract

Interactive event-driven programs are structured and executed using two types of constructs: interconnectable processing components and flow objects with associated data. Components are interconnected in a hierarchical dataflow network, and references which provide access to flow objects flow on the interconnections. Response to events and bidirectional coordination over multicomponent data paths, even in a distributed object system, employ unidirectional dataflows and intercomponent message sequences mediated by flow objects. Scaling and abstraction of complexity are facilitated by encapsulation of constructed networks into new component definitions. An interactive debugger preserves state as an executing program is edited, permitting an event-driven program to be modified in the intervals between processing of events without reinitialization. A component protection method employs multiple Levels of usage authorization within components, enabling developers to define and distribute new protected components in a decentralized component market.

Claims

1. A method of processing data comprising

providing a flow object,

providing a network of interconnected processing components none of which is a flow object and at least one of which is not a user-interface component,

associating the flow object with data that has been or is to be processed,

enabling a flow within the network which transports from one processing component to another a reference which provides access to the flow object,

enabling processing components to use the reference to obtain access to the flow object for the purpose of processing the flow object or the data associated with the flow object, and

maintaining consistency across the network, as the flow object or the data associated with it are processed, of the components'"'"' views of the flow object and its data, by a sequence of communications which comprises

a communication from a sending processing component to the flow object, and

a communication from the flow object to a receiving processing component.

2. The method of claim 1 wherein

an interconnection touches a pair of processing components associated with the interconnection, and

a reference which provides access to the flow object is transported across the interconnection.

3. The method of claim 2 wherein references which provide access to the same flow object are transported across different interconnections.

4. The method of claim 2 wherein the reference which provides access to the flow object is transported in only one direction across the interconnection, from a sending component associated with the interconnection, which component sends the flow, to a receiving component associated with the interconnection, which component receives the flow.

5. The method of claim 4 wherein the sending processing component is the processing component associated with the flow object'"'"'s owner.

6. The method of claim 4 comprising a selector processing component, wherein

the selector processing component is a receiving component of a reference which provides access to an input flow object whose associated data comprises a base collection, and

the selector processing component is a sending component of a reference which provides access to a list flow object whose associated data comprises a selected collection instance based on the base collection.

7. The method of claim 6 in which the selector processing component is a sending component of a reference which provides access to an output flow object, wherein

the associated data of the output flow object provides access to the subcollection of the base collection specified by the selected collection instance associated with the list flow object, and

a modification to the selected collection instance causes the value of the associated data of the output flow object to update to provide access to the subcollection specified by the modified selected collection instance.

8. The method of claim 7 wherein

the output flow object has an owner, and

the selector processing component is associated with the owner of the output flow object.

9. The method of claim 6 wherein

the list flow object has an owner, and

the selector processing component is associated with the owner of the list flow object.

10. The method of claim 4 comprising a launcher processing component, wherein

the launcher processing component is configured to be a receiving component of a reference which provides access to an argument flow object,

the launcher processing component is configured to be a receiving component of a reference which provides access to a flow object whose associated data denotes an instantiable processing component type,

an instance of the instantiable processing component type is configured to be a receiving component of a reference which provides access to a flow object, and

the launcher processing component is configured to perform an instantiation processing operation, wherein

the instantiation processing operation causes to be created an instance of the instantiable processing component type, and

if the launcher processing component is a receiving component of a reference which provides access to an argument flow object, then the created instance is a receiving component of a reference which provides access to said argument flow object.

11. The method of claim 4 wherein, when the receiving component receives a reference which provides access to the flow object, then the receiving component is enabled to process the flow object or its associated data.

12. The method of claim 4 wherein,

when a processing component of the network which is configured to be both a receiving component and a sending component receives a flow of a reference which provides access to the flow object,

then the processing component is enabled to send a flow of a reference which provides access to the flow object.

13. The method of claim 4 wherein

a processing component A of the network is a sending component with respect to the flow object and with respect to interconnection I, and

a processing component B of the network is a receiving component with respect to the flow object and with respect to interconnection J, wherein

interconnection I is different from interconnection J.

14. The method of claim 4 comprising a composite processing component which comprises an internal network of interconnected processing components, wherein

if the composite processing component receives a flow which transports a reference A which provides access to flow object F, then there exists a processing component of the integral network which receives a flow which transports a reference B which provides access to flow object F, and

if the composite processing component sends a flow which transports a reference C which provides access to flow object G, then there exists a processing component of the internal network which sends a flow which transports a reference D which provides access to flow object G.

15. The method of claim 4 comprising

a processing component configured to be a sending component with respect to an interconnection, and

a processing operation of the processing component, a result of which processing operation is a result object, wherein

upon completion of the processing operation, the processing component is enabled to initiate a flow of a reference which provides access to a flow object whose associated data comprises the result object.

16. The method of claim 1 wherein processing comprises modification of an aspect of the flow object or of the data associated with the flow object.

17. The method of claim 1 wherein a reference which provides access to the flow object is used by one of the processing components to communicate to the flow object.

18. The method of claim 1 wherein a reference which provides access to one of the processing components is used by the flow object to communicate to the processing component.

19. The method of claim 1 wherein

the flow object has an owner and comprises a reference which provides access to the owner, and

the owner is associated with one of the processing components.

20. The method of claim 19 wherein the owner comprises the owner'"'"'s associated processing component and an interconnection which touches that processing component.

21. The method of claim 19 wherein one of the processing components which is processing the flow object or the data associated with the flow object maintains consistency between itself and the processing component associated with the owner of the flow object.

22. The method of claim 19 wherein the processing component associated with the owner maintains consistency between itself and the processing component associated with a dependent of the flow object.

23. The method of claim 22 wherein the processing component associated with the dependent is configured to ignore an aspect of a received communication.

24. The method of claim 19 wherein the owner comprises a processing component of the network.

25. The method of claim 19 wherein the owner is associated with exactly one processing component of the network.

26. The method of claim 19 wherein the owner is configured to interact with its associated processing component.

27. The method of claim 1 wherein the flow object has one or more dependents and comprises one or more references which provide access to the one or more dependents, wherein

each of the dependents is associated with one of the processing components.

28. The method of claim 27 wherein a dependent comprises the dependent'"'"'s associated processing component and an interconnection which touches that processing component.

29. The method of claim 27 wherein the flow object communicates to the processing component respectively associated with each of its dependents.

30. The method of claim 27 wherein a dependent comprises a component of the network.

31. The method of claim 1 wherein a flow comprises copying a reference which provides access to the flow object.

32. The method of claim 1 wherein at least one of the communications comprises giving notice that processing has occurred.

33. The method of claim 1 wherein processing comprises projecting an aspect of the flow object or data associated with the flow object onto a user interface.

34. The method of claim 33 wherein for every displayed element of the user interface there exists a flow object wherein the displayed element is a projection of an aspect of the flow object or of data associated with the flow object.

35. The method of claim 1 wherein one of the processing components is configured to receive an event.

36. The method of claim 35 wherein the event comprises a signal originated by a device.

37. The method of claim 1 wherein the components of the network are arranged hierarchically.

38. The method of claim 1 wherein the data associated with the flow object comprises an object.

39. The method of claim 38 wherein the object comprises a process.

40. The method of claim 1 wherein the data associated with the flow object comprises a flow object.

41. The method of claim 1 wherein the data associated with the flow object comprises a collection of flow objects.

42. The method of claim 1 wherein the association between the flow object and its associated data comprises the flow object comprising a reference which provides access to the associated data.

43. The method of claim 1 wherein more than one flow object is associated with the same data.

44. The method of claim 33 wherein the associated data of the created flow object is created other than by the processing component which creates the flow subject.

45. The method of claim 1 wherein the data associated with a first flow object has a nonempty intersection with the data associated with a second flow object.

46. The method of claim 1 wherein at least some of the processing components of the network are organized in types, instances of which comprise these processing components.

47. The method of claim 1 wherein at least some of the processed data are organized in types, instances of which comprise these processed data.

48. The method of claim 47 wherein one of the data instances denotes a processing component type.

49. The method of claim 48 wherein one of the processing components of the network creates an instance of the denoted processing component type.

50. The method of claim 49 wherein the processing component initiates the execution of the created component instance.

51. The method of claim 47 comprising a selected collection processed data type, an instance of which comprises

a reference which provides access to a base collection on which the selected collection instance is based, and

a selection on the base collection, which selection comprises a specification of a possibly empty subcollection of the base collection.

52. The method of claim 51 comprising a flow object associated with an instance of the selected collection processed data type, wherein

there is an editor processing component of the network which is configured to modify the selection in the flow object'"'"'s associated selected collection instance, and

there is a projector processing component of the network which is configured to project onto a user interface an aspect of the selected collection instance.

53. The method of claim 52 wherein a modification to the selected collection instance causes the projector processing component to respond by updating its projection to be consistent with the resulting value of the selected collection instance.

54. The method of claim 1 comprising a flow object whose response to processing is consistent with the response to said processing of a null object.

55. The method of claim 1 wherein one of the processing components is configured to create a flow object.

56. The method of claim 43 wherein the processed data comprises the settable processing component'"'"'s setting value.

57. The method of claim 56 wherein

there is a flow object whose associated processed data comprises an aspect of the settable processing component'"'"'s setting value, and

there is an operating processing component of the network configured to process said flow object or associated processed data.

58. The method of claim 57 wherein

the flow object has an owner associated with an owning processing component of the network, a dependent associated with a user processing component of the network, and a dependent associated with the operating processing component, and

the owning processing component, the operating processing component, and the user processing component participate in a consistency-maintaining sequence of coordinations.

59. The method of claim 58 wherein the owning processing component is the settable processing component.

60. The method of claim 55 wherein a creator processing component which creates the flow object is configured to send a flow of a reference which provides access to the flow object.

61. The method of claim 60 wherein the created flow object has an owner and the owner is configured to enable performance of a processing operation by a user processing component of the network which comprises a reference which provides access to the flow object.

62. The method of claim 61 wherein the owner is associated with the creator processing component.

63. The method of claim 1 wherein the flow object yields an identifier which is distinctive of the flow object.

64. The method of claim 63 wherein the distinctive identifier may be data or an object.

65. The method of claim 63 wherein one of the processing components uses the identifier in processing.

66. The method of claim 65 wherein processing comprises projection of an aspect of the identifier onto a user interface.

67. The method of claim 65 wherein processing comprises a table lookup.

68. The method of claim 1 wherein the flow object comprises a reference which provides access to a processing component of the network.

69. The method of claim 1 wherein the processing components of the network include a settable processing component which comprises a setting value.

70. The method of claim 69 wherein the setting value becomes persistent when the network is encapsulated.

71. The method of claim 70 wherein the setting value may be changed either before or after encapsulation.

72. The method of claim 1 wherein at least some of the flow objects are organized in types, instances of which comprise these flow objects.

73. The method of claim 1 wherein there is a proxy object which is in relationship to the flow object.

74. The method of claim 73 wherein a processing component of the network communicates to the flow object by communicating to the proxy object which forwards the communication to the flow object and returns the result to the processing component.

75. The method of claim 73 wherein the flow object communicates to the processing component by communicating to the proxy object, which forwards the communication to the processing component and returns the result to the flow object.

76. The method of claim 75 wherein the flow object has an owner and communicates to the processing component associated with the owner via the proxy object.

77. The method of claim 75 wherein the flow object has a dependent and communicates to the processing component associated with the dependent via the proxy object.

78. The method of claim 73 wherein

at least one communication is sent via a proxy object.

79. The method of claim 1 wherein

there is an editor processing component of the network which is configured to modify aspect A of the flow object or the flow object'"'"'s associated processed data, and

there is a user processing component of the network which is configured to employ aspect B in processing of the flow object or of the flow object'"'"'s associated processed data.

80. The method of claim 79 wherein there occurs a consistency-maintaining sequence of coordinations comprising

coordination between the editor processing component and a relay processing component of the network, wherein the editor processing component notifies the relay processing component, by a sequence of communications, that modification has occurred, and

coordination between the relay processing component and the user processing component wherein the relay processing component notifies the user processing component, by a sequence of communications, that modification has occurred.

81. The method of claim 80 wherein the user processing component is configured so that, in response to notice that modification has occurred, the user processing component employs in its processing the modified flow object or its associated modified data.

82. The method of claim 1 comprising a command flow object which has

an owner associated with an actuator processing component of the network, configured to perform a designated processing operation, and

a dependent associated with an initiator processing component of the network, configured to receive a signal, wherein

when the initiator processing component receives the signal it notifies the actuator processing component, by a sequence of communications, that the signal has been received, and

the actuator processing component performs the designated processing operation.

83. The method of claim 82 wherein the signal arises in consequence of a processing operation.

84. The method of claim 82 comprising a projector processing component which projects an aspect of the command flow object or its associated data on a user interface, wherein the occurrence of an event at the user interface causes the initiator processing component to receive a signal.

85. The method of claim 84 wherein the projector processing component is the initiator processing component.

86. A tool for developing a software program,

the tool comprising a program under development and a possibly null flow object,

the program under development comprising a network comprising components and interconnections,

the tool being configured to restructure the network,

an interconnection denoting a flow object and being attached to two components, one of the attachments being asource and the other being a sink, the source being associated with a source function,

an output from the source function determining the flow object denoted by the interconnection,

an input to the source function comprising a flow object denoted by a sink of the source'"'"'s component, and

a nonnull flow object comprising a processed object, wherein

a component is configured to send a processing message to the processed object,

a component is configured to communicate to the nonnull flow object denoted by an interconnection attached to the component, and

a component is configured to enable the nonnull flow object denoted by an interconnection attached to the component to communicate to the component.

87. The tool of claim 86 comprising a program control mechanism configured to stop and start the program under development, wherein

when the program under development is stopped, the interconnection denotes a null flow object.

88. The tool of claim 86 wherein a network computation comprises a source function, the network computation being configured so that execution of the network computation is begun when the program under development is started, wherein

if the network computation terminates without error and then the network is restructured

then the network computation is reconfigured based on the resultant network structure, and execution of the resultant network computation is begun if the program is not stopped.

89. The tool of claim 88 wherein the network computation is iterative.

90. The tool of claim 88 wherein all functions of the network computation are performed, one function at a time.

91. The tool of claim 90 wherein, if the value of a function is dependent on the value of at most one input, then the function is evaluated whenever that input value changes.

92. The tool of claim 90 wherein, if the value of a function is dependent on the value of more than one input there is a pending status associated with the function, wherein

the pending status of the function is set to pending if the value of an input on which the value of the function is dependent changes when the pending status of the function is not pending,

the pending status of the function is set to not pending when the program under development is stopped, and

the pending status of the function is set to not pending when the function'"'"'s evaluation is complete.

93. The tool of claim 92 wherein the network computation does not terminate until the pending status of every function of the network computation is not pending.

94. The tool of claim 93 comprising a network computation control mechanism which seeks to minimize the total number of function evaluations.

95. The tool of claim 92 wherein a designator of the function is placed at the rear of a first-in first-out queue when the pending status of the function is set to pending, and the function designator is removed when it reaches the front of the queue, after which removal the function is evaluated.

96. The tool of claim 95 wherein the network computation has terminated when the queue is empty after completion of evaluation of the function.

97. The tool of claim 95 comprising loop detection to determine nontermination of the computation.

98. The tool of claim 88 comprising a network computation control mechanism which seeks to minimize the total network computation time.

99. The tool of claim 88 wherein the network computation also comprises a state function.

100. The tool of claim 88 wherein the network computation comprises all source functions and all state functions of the network.

101. The tool of claim 88 wherein a function of the network computation is configured to query a database.

102. The tool of claim 86 comprising a connector, wherein

the connector is attached to a component,

the connector comprises either a sink connector or a source connector, wherein

either the source connector comprises a source, in which case the source connector is attached to the source'"'"'s interconnection, the source connector denotes the flow object denoted by the interconnection, and the source connector comprises the source'"'"'s source function, or else the source connector is not attached to an interconnection, and

either the sink connector comprises a sink, in which case the sink connector is attached to the sink'"'"'s interconnection and the sink connector denotes the flow object denoted by the interconnection, or else the sink connector is not attached to an interconnection.

103. The tool of claim 86 wherein the program under development comprises a user interface.

104. The tool of claim 86 comprising a composite component type which comprises a network of component templates and interconnection templates, wherein

each interconnection template has two attached component templates,

said composite component type being configured to create an instance which is a composite component comprising a network of components and interconnections, wherein

a component template creates a component

an interconnection template creates an interconnection, and

the components attached to the interconnection are created by the component templates attached to the interconnection template which creates the interconnection.

105. The tool of claim 104 wherein a component template comprises either a composite component template or a primitive component template.

106. The tool of claim 105 wherein a composite component template comprises a composite component type, and a primitive component template comprises a primitive component type.

107. The tool of claim 106 wherein a component type comprises either a composite component type or a primitive component type.

108. The tool of claim 107 comprising a restriction mechanism wherein the component type comprises a restriction.

109. The tool of claim 108 wherein an instance of the type comprises the restriction.

110. The tool of claim 104 wherein the instance is attached to an outside sink connector.

111. The tool of claim 110 wherein the network of the instance comprises a component attached to an inside sink connector, wherein

the inside sink connector and the outside sink connector denote the same flow object.

112. The tool of claim 104 wherein the instance is attached to an outside source connector.

113. The tool of claim 112 wherein the network of the instance comprises a component attached to an inside source connector, wherein

the inside source connector and the outside source connector denote the same flow object.

114. The tool of claim 86 in which the program under development comprises an instance of a composite component type.

115. The tool of claim 86 configured to create an instance of a component type.

116. The tool of claim 86 whose program under development comprises at least one component with a source connector which, upon commencement of the program, denotes a nonnull flow object.

117. The tool of claim 86 wherein every component of the program under development is created by a component template.

118. The tool of claim 117 wherein a component'"'"'s template'"'"'s type determines the number of sink and source connectors and the identity of each sink and source connector of the component.

119. The tool of claim 118 wherein the type of the component determines the source function of each source connector of the component.

120. The tool of claim 119 wherein the source function'"'"'s input comprises either or both of a flow object denoted by a sink of the source'"'"'s component or a state variable of the component.

121. The tool of claim 86 wherein the program under development comprises a component which comprises a state variable.

122. The tool of claim 121 wherein the identity and initial value of the state variable are determined by the component'"'"'s type.

123. The tool of claim 122 wherein the state variable is set to its initial value when the program is stopped.

124. The tool of claim 122 wherein the state variable is associated with a state function, determined by the components type, the output from the state function determining the state variable'"'"'s value and the input to the state function comprising either or both of a flow object denoted by a sink of the source'"'"'s component or a state variable of the component.

125. The tool of claim 121 wherein the state variable provides access to a storage system external to the component.

126. The tool of claim 86 wherein the state variable provides access to the result of a database query.

127. The tool of claim 121 wherein the component projects an aspect of the state variable onto the user interface of the program under development.

128. The tool of claim 86 in which the program under development comprises a component which comprises a setting variable.

129. The tool of claim 128 wherein the component'"'"'s type determines the identity of the setting variable.

130. The tool of claim 128 wherein the initial value of the setting variable is determined by the template from which the component is created.

131. The tool of claim 130 wherein the setting variable is set to its initial value when the program is stopped.

132. The tool of claim 128 wherein a source function'"'"'s input comprises a flow object denoted by a sink of the source'"'"'s component or the value of a state variable of the component or the value of the setting variable, and a state function'"'"'s input comprises a flow object denoted by a sink of the source'"'"'s component or the value of a state variable of the component or the value of the setting variable.

133. The tool of claim 86 wherein the processed object comprises a state variable.

134. The tool of claim 86 wherein the processed object comprises a setting variable.

135. The tool of claim 86 wherein a component is configured to receive an event.

136. The tool of claim 135 wherein the event is sent by the tool.

137. The tool of claim 135 wherein the event is sent by the user interface of the program under development.

138. The tool of claim 135 wherein the component comprises a state variable whose value is modified by the component'"'"'s receipt of the event.

139. The tool of claim 86 wherein the program under development comprises a communication mechanism in which an aspect of one component is configured to communicate with an aspect of another component.

140. The tool of claim 86 wherein a function of the network computation is configured to modify an aspect of the processed object.

141. The tool of claim 86 comprising a developer interface.

146. The tool of claim 86 comprising a data inspection mechanism wherein an aspect of any of a state variable, a setting variable, or a flow object is projected onto the developer interface.

147. The tool of claim 86 comprising a program inspection mechanism wherein an aspect of the network is projected onto the developer interface.

148. The tool of claim 86 comprising a stepping mechanism configured to control and inspect the progress of the network computation.

149. The tool of claim 148 wherein the stepping mechanism cooperates with the program inspection mechanism to project on the developer interface information which visually depicts the state changes of the program under development.

150. The tool of claim 86 comprising a type library comprising a component type.

151. The tool of claim 86 wherein an input of a function of the network computation comprise an aspect of the processed object.

142. The tool of claim 142 wherein the developer interface comprises the user interface of the program under development.

143. The tool of claim 142 comprising a selection mechanism configured to choose a portion of the network on which an operation is to be performed.

144. The tool of claim 143 wherein the restriction mechanism interacts with the menu mechanism to modify either the availability of an opportunity to perform an operation on the portion of the network or the behavior of the operation.

145. The tool of claim 142 comprising a menu mechanism configured to present an opportunity to perform an operation.