User interface > Main menu > Menu: Help > Character class calculator
The character class calculator is made to construct character classes step by step, by adding or subtracting characters from the actually resulting class.
The characters, which shall be added or removed, can be selected from a list of predefined character classes or they can be put in as a range or a list of characters or an individual character.
The same rules as for the characters of a string apply to the literal character list. E.g. line breaks '\n' also can be inserted. The backslash character must therefore also be doubled: \\, to insert it into a list.
The button marked with '+' in the tool bar of the character class calculator
is used to add characters to the resulting class. The characters to be added must have been selected before by means of the dialog elements below.
The button marked with '-' in the tool bar of the character class calculator
is used to remove characters from the resulting class The characters to be removed must have been selected before by means of the dialog elements below. If characters are selected which don't exist in the result class, then this doesn't have any consequence.
The button marked with 'x'
deletes the previous selection.
The result can be represented as
compressed
Characters are summarized into character classes provided that the set is complete. The remaining characters are represented as ranges or single characters.
list of ranges
Characters succeeding one another in the ANSI table are summarized to ranges. E.g. the range of 1-6. results from 1,2,3,4,5,6. The remaining characters are listed one by one.
Whether the characters are put into a range expression or not also depends on the following setting
minimal distance for character ranges
Characters are put into a range expression only when in accordance with the ANSI list at least so many other characters are situated between the smallest and the greatest character as the minimal distance is demanding.
enumeration
All characters are listed one by one..
With the longish button above the result list: all characters, which are not in the actual result, you can invert the previous result. So all characters are listed, which were not selected before.
If the dialog is exited with Ok, a second dialog appears, where you can enter the number of characters, which shall follow each other.
After pressing Ok a second time, the resulting expression will be copied into the clipboard.
Example:
The Wikipedia dokumentation :
http://en.wikipedia.org/wiki/Wikipedia:How_to_edit_a_page
defines:
In the URL, all symbols must be among:
A-Z a-z 0-9 . _ \ / ~ % - + & # ? ! = ( ) @ \x80-\xFF
To construct this character set, you have to:
1. add the character set: "any word character - all alphanumeric characters plus the underscore"
2. add the character range from Hex 80 to Hex ff
3. add the character list: ".\\/~%+-&#?!=()@"
Caution: the list may not contain white spaces and the backslash has to be doubled.
If you are pressing Ok now and let the unlimited repeat, the result is:
[-[:word:]€-ÿ!#%&()+./=?@\\~]+
The hyphen appears in front of the expression, as it shall not characterize a range.