Context-free grammar

• US 20080097744A1
• Filed: 10/20/2006
• Published: 04/24/2008
• Est. Priority Date: 10/20/2006
• Status: Active Grant

• Current Assignee: Adobe Inc.
• Original Assignee: Adobe Systems Incorporated (Adobe Inc.)
• Inventors: Levy, Philip
• Granted Patent: US 8,397,157 B2
• Time in Patent Office: Days
• US Class Current: 704/4
• CPC Class Codes: G06F 40/143 Markup, e.g. Standard Generalized Markup Language [SGML] or Document Type Definition [DTD]
• CPC Class Codes: G06F 40/211 Syntactic parsing, e.g. based on context-free grammar [CFG] or unification grammars
• CPC Class Codes: G06F 40/221 Parsing markup language streams streaming G06F40/149
• CPC Class Codes: G06F 40/56 Natural language generation

Abstract

In one embodiment, a method comprising accessing a first data object and a second data object of a data structure representing electronic content, the second data object being associated with the first data object, selecting, based on first content included in the first data object, a grammar rule included in a grammar, the grammar rule including a grammar rule item, and based on second content included in the second data object, selecting the grammar rule item included in the grammar rule, and based on the second content and the grammar rule item, generating a portion of a textual representation of the electronic content.

Claims

1. A method comprising:

accessing a first data object and a second data object of a data structure representing electronic content, the second data object being associated with the first data object;

selecting, based on first content included in the first data object, a grammar rule included in a grammar, the grammar rule including a grammar rule item;

based on second content included in the second data object, selecting the grammar rule item included in the grammar rule; and

based on the second content and the grammar rule item, generating a portion of a textual representation of the electronic content.

2. The method of claim 1, wherein the second data object is a direct child of the first data object.

3. The method of claim 1, wherein the second data object is an indirect child of the first data object.

4. The method of claim 1, wherein the grammar rule includes a plurality of grammar rule items.

5. The method of claim 1, wherein the grammar rule includes a rule-level pre-processing instruction, and wherein the method further includes executing the rule-level preprocessing instruction in response to the selection of the grammar rule.

6. The method of claim 1, wherein the grammar rule includes a rule-level post-processing instruction, and wherein the method further includes executing the rule-level preprocessing instruction after the generation of the portion of the textual representation.

7. The method of claim 1, wherein the second data object is contained in the first data object.

8. The method of claim 1, wherein the first content included in the first data object includes a type of the second data object, the type matching a type of the grammar rule.

9. The method of claim 1, wherein the grammar rule item includes output control instructions, and wherein the generating of the portion of the textual representation is according to the output control instructions.

10. The method of claim 9, wherein the portion of the textual representation includes content generated from the second content according to the output control instructions.

11. The method of claim 9, wherein the output control instructions are literally included within the grammar rule item.

12. The method of claim 9, wherein the output control instructions are implicit in the grammar rule item.

13. The method of claim 1, wherein the selecting of the grammar rule includes accessing a type of the second data object and matching a type of the grammar rule to the type of the second data object.

14. The method of claim 1, wherein the electronic content is an electronic document.

15. The method of claim 1, wherein the content of the data structure includes the second content.

16. The method of claim 1, wherein the second data object is included within the first data object.

17. The method of claim 1, wherein the second data object is a separate object from the first data object.

18. The method of claim 1, wherein the grammar rule is composed by inclusion of a plurality of grammar rules.

19. a method comprising:

accessing a textual representation of electronic content, the textual representation including a first textual element semantically containing a second textual element;

based on at least the first textual element;

selecting a grammar rule having a grammar rule item; and

creating a data object;

based on at least first content in the second textual element, selecting the grammar rule item;

associating, according to the grammar rule item, a data element with the data object, the data element including second content in the second textual element.

20. The method of claim 19, wherein the grammar rule is composed by inclusion of a plurality of grammar rules.

21. The method of claim 19, wherein the selection of the grammar rule is further based on the second textual element.

22. The method of claim 19, wherein the selection of the grammar rule is not based on the second textual element.

23. The method of claim 19, wherein the grammar rule item includes output control instructions and the selecting of the grammar rule item is based upon determining that the second textual element is generable according to the output control instructions.

24. The method of claim 23, wherein the output control instructions are explicitly included in the grammar rule item.

25. The method of claim 23, wherein the output control instructions are implicit in the grammar rule item.

26. The method of claim 19, wherein the data element is a scalar data element.

27. The method of claim 19, wherein the data element is a compound data element.

28. The method of claim 27, wherein the data element is a data object.

29. The method of claim 19, wherein the grammar rule item includes an identifier and wherein the selecting of the grammar rule item is further based on the first content matching the identifier.

30. The method of claim 29, wherein the associating of the data element with the data object is facilitated by the identifier.

31. The method of claim 29, wherein the identifier is a name of the grammar rule.

32. The method of claim 19, wherein the first textual element is a first markup language opening tag paired with a markup language closing tag, and wherein the second textual element is a second markup language opening tag located in the textual representation between the first markup language opening tag and the markup language closing tag and located within the next containment level below the first textual element.

33. The method of claim 19, wherein the textual representation is stored on a computer-readable medium.

34. The method of claim 19, wherein the grammar rule has an object type, and the data object is suited to the object type.

35. The method of claim 19, wherein the first content and the second content are the same content.

36. The method of claim 19, wherein the grammar rule is composed by inclusion of a plurality of grammar rules.

37. A system comprising:

a grammar store including a grammar rule, the grammar rule including a grammar rule item;

a data structure parsing module to access a first data object and a second data object of a data structure representing electronic content, the second data object being associated with the first data object, to select, based on first content included in the first data object, the grammar rule, to select, based on second content of the second data object, the grammar rule item, and to generate, based on the second content and the grammar rule item, a portion of a first textual representation of the electronic content;

a textual representation parsing module to access a second textual representation of electronic content, the second representation including a first textual element semantically containing a second textual element, to select the grammar rule and to create a third data object, the selection of the grammar rule and the creation of the third data object being based on at least the first textual element, to select, based on at least third content in the second textual element, the grammar rule item, and to associate, according to the grammar rule item, a data element with the third data object, the data element including fourth content in the second textual element.

38. The system of claim 37, wherein the grammar rule includes a plurality of grammar rule items.

39. The system of claim 37, wherein the grammar rule includes a rule-level preprocessing instruction, and wherein the data structure parsing module is to execute the rule-level preprocessing instruction in response to the selection of the grammar rule.

40. The system of claim 37, wherein the grammar rule includes a rule-level postprocessing instruction, and wherein the data structure parsing module is to execute the rule-level preprocessing instruction after the generation of the portion of the textual representation.

41. The system of claim 37, wherein the second data object is contained in the first data object.

42. The system of claim 37, wherein the first content included in the first data object includes a type of the second data object, the type matching a type of the grammar rule.

43. The system of claim 37, wherein the grammar rule item includes output control instructions.

44. The system of claim 43, wherein the data structure parsing module is to generate the portion of the first textual representation according to the output control instructions.

45. The system of claim 44, wherein the portion of the first textual representation includes content generated from the second content according to the output control instructions.

46. The system of claim 43, wherein the output control instructions are literally included within the grammar rule item.

47. The system of claim 43, wherein the output control instructions are implicit in the grammar rule item.

48. The system of claim 43, wherein the textual representation parsing module is to select the grammar rule item based upon determining that the second textual element is generable according to the output control instructions.

49. The system of claim 37, wherein the data structure parsing module is to access a type of the second data object and to match a type of the grammar rule to the type of the second data object.

50. The system of claim 37, wherein the electronic content is an electronic document.

51. The system of claim 37, wherein the content of data structure includes the second content.

52. The system of claim 37, wherein the data element is a scalar data element.

53. The system of claim 37, wherein the data element is a compound data element.

54. The system of claim 53, wherein the data element is a data object.

55. The system of claim 37, wherein the grammar rule item includes an identifier and wherein the textual representation parsing module is to select the grammar rule item further based on the first content matching the identifier.

56. The system of claim 55, wherein the associating of the data element with the data object is facilitated by the identifier.

57. The system of claim 37, wherein the first textual element is a first markup language opening tag paired with a markup language closing tag, and wherein the second textual element is a second markup language opening tag located in the second representation between the first markup language opening tag and the markup language closing tag and located within the next containment level below the first textual element.

58. The system of claim 37, wherein the second representation is stored on a computer-readable medium.

59. The system of claim 37, wherein the grammar rule has an object type, and the data object is suited to the object type.

60. The system of claim 37, wherein the third content and the fourth content are the same content.

61. A system including:

means for accessing a first data object and a second data object of a data structure representing electronic content, the second data object being associated with the first data object;

means for selecting, based on first content included in the first data object, a grammar rule included in a grammar, the grammar rule including a grammar rule item;

means for selecting, based on second content included in the second data object, the grammar rule item included in the grammar rule; and

means for generating, based on the second content and the grammar rule item, a portion of a textual representation of the electronic content.

62. A system including:

means for accessing a textual representation of electronic content, the textual representation including a first textual element semantically containing a second textual element;

means for selecting, based on at least the first textual element, a grammar rule having a grammar rule item;

means for creating, based on at least the first textual element, a data object;

means for selecting, based on at least first content in the second textual element, the grammar rule item;

means for associating, according to the grammar rule item, a data element with the data object, the data element including second content in the second textual element.

63. A machine-readable medium embodying instructions, which when executed by a machine, cause the machine to perform a method including:

accessing a first data object and a second data object of a data structure representing electronic content, the second data object being associated with the first data object;

selecting, based on first content included in the first data object, a grammar rule included in a grammar, the grammar rule including a grammar rule item;

based on second content included in the second data object, selecting the grammar rule item included in the grammar rule; and

based on the second content and the grammar rule item, generating a portion of a textual representation of the electronic content.

64. A machine-readable medium embodying instructions, which when executed by a machine, cause the machine to perform a method including:

accessing a textual representation of electronic content, the textual representation including a first textual element semantically containing a second textual element;

based on at least the first textual element;

selecting a grammar rule having a grammar rule item; and

creating a data object;

based on at least first content in the second textual element, selecting the grammar rule item;

associating, according to the grammar rule item, a data element with the data object, the data element including second content in the second textual element.