Global regular expression backreferences

摘要

A system and a method are provided for querying a knowledge resource. The querying system is configured for executing queries in a query language that accepts global backreferences that are not limited to a being located in the condition including a regular expression (regex) to which the global backreference refers. In the method, an input query is received, a query based thereon containing one or more global backreferences is executed, and results are retrieved. One condition of the query includes a regex that identifies strings that match the regex. The regex includes one or more capturing groups for capturing substrings of an identified matching string. The global backreference retrieves the captured substring(s). Each global backreference in the query can be a remote backreference, which is outside the regex condition to which it refers, or a local backreference, which is in the same condition as the regex.

主权项

1. A method for querying a knowledge resource comprising:
providing a querying system which is configured for executing queries in a query language that accepts global backreferences that are not limited to being located in a respective condition which includes a regular expression to which the global backreference refers; receiving an input query which seeks information from the knowledge resource; with the querying system, based on the input query, executing a query containing a global backreference comprising retrieving results from the knowledge resource responsive to the query, the query including a set of conditions, a first of the conditions including a regular expression that identifies strings in the knowledge resource that match the regular expression, the regular expression including a capturing group for capturing a substring of an identified matching string, the global backreference retrieving the substring captured by the capturing group and wherein the global backreference comprises a remote backreference which is outside the first condition; and outputting at least one of the results of the query containing the global backreference and information based on the results.