(Message archives/pasadena:18) Return-Path: a.ks.id.ethz.ch!pasadena Return-Path: Received: by crane.aa.ox.com (/\=-/\ Smail3.1.18.1 #18.26) id ; Mon, 29 Jul 91 04:35 EDT Received: from ural-gw by bernina.ethz.ch with SMTP inbound id <10016-0@bernina.ethz.ch>; Mon, 29 Jul 1991 10:34:53 +0200 Date: Mon, 29 Jul 91 10:34:48 +0200 From: Pasadena Server Message-Id: <9107290834.AA23649@ural> Received: by ural id AA23649; Mon, 29 Jul 91 10:34:48 +0200 To: emv@ox.com Subject: Help @(#)exclude 1.2 90/10/04 15:55:20 P A S A D E N A Last change 90/10/04 -_-_-_-_-_-_-_- EXCLUDE ======= This command adds a filtering stage to your query. It provides a separate, powerful mechanism for eliminating unwanted articles than changing the query text. The syntax of the command is: USE EXCLUDE [] [] [] ... END where is the name of the query to which this EXCLUDE should be added, and is defined as follows [1]: A regular-expression specifies a set of character strings to be matched. Regular expressions can be built up from the following single-character regular expressions: c Any ordinary character not listed below. An ordinary character matches itself. \ Backslash; when followed by a special character, the regular expression matches the "escaped" character. . Dot; Matches any single character except NEWLINE. [ccc] A nonempty string of characters, enclosed in square brackets matches any single character in the string. For example, [abcxyz] matches any single character from the set 'abcxyz' at the current position. When the first character of the string is a caret (^), the regular expression matches any character *EXCEPT* those in the remainder of the string. [l-r] The minus sign, between two characters in square brackets indicates a range of consecutive ASCII characters to match. For example, the range [0-9] is equivalent to the string [0123456789]. A concatenation of regular expressions matches a concatenation of text strings. * A single-character regular expression, followed by an asterisk * matches zero or more occurences of the single-character regular expression. Such a pattern is called a transitive closure. For example, [a-z][a-z]* matches any string of one or more lower-case characters. (n) A single-character regular expression, followed by an integer in parenthesis, matches n occurences of the single-character regular expression. Such a pattern is called a repeater. For example, [a-z](3) matches all lower-case trigrams. Examples: 1. Sending this command to pasadena@inf.ethz.ch USE hackers EXCLUDE From: *knuth@.*[Ss]tanford.[Ee][Dd][Uu].* From: *dsr@.*[Aa][Tt][Tt].[Cc][Oo][Mm].* END excludes all messages from Donald Knuth and Dennis Ritchie. The first regular expression first matches the text "From:" then zero or more spaces, then the text "knuth@" then zero or more characters, then the text "stanford.edu" (ignoring case for S and EDU) and finally all characters after it. Both of the following text strings would match this first regular expression: From: "Donald Knuth"