Instead, A regex of ^415\-5553\-7676$ would be more precise and easier to read, resulting in the three digits 415 followed by a minus sign, three times the number 5 followed by a 3, another minus sign, and then two times the sequence of digits 76 including characters for the beginning of the line ( ^) and the end of the line ( $). According to this regular expression, the digits can be arbitrary and the pattern can include other characters because the regex does not use delimiters such as \b for word boundary, ^ for beginning of line, and $ for end of line. Not only does it match the above string, but it also matches other strings, such as 123-4567-8901 or foo-123-5553-7676-bar. However, this generated regex lacks precision. The generated regex shown in Listing 2 does the trick: a pattern consisting of three digits, followed by a minus sign, four digits, another minus sign, and another four digits. You can then save and run the regular expression as rg.py ( Listing 2). Listing 1 shows a short script for RegexGenerator, which determines a regular expression for the string 415-5553-7676. For Python, I found RegexGenerator and its associated regex-generator-lib. In looking for libraries that work similarly to the other tools discussed in this article, my research turned up limited results. Like rgxg, txt2regex formulates regular expressions with maximum precision by using parameters to adapt the expression to your specified pattern. This is a big help because various implementations and dialects are found in everyday Linux: regular expressions, extended regular expressions, and Perl-Compatible Regular Expressions (PCRE). ![]() Txt2regex provides an overview of how you need to specify the regular expression in the respective tool for it to recognize the pattern. As you use txt2regex, you will learn to specify the pattern sequence precisely. This is an intermediate step in querying for the desired string. You then select the corresponding letter from the list ( Figure 6) to generate the regular expressions in the desired dialect ( Figure 7).įigure 7: Txt2regex generates patterns for the selected dialects. You can access a complete list of dialects by typing a forward slash. Based on the input, txt2regex assembles the expression for various tools, such as awk, find, grep, PHP, and PostgreSQL. Txt2regex offers a helping hand when generating regular expressions by asking questions about the characters, including how many characters follow each other. When txt2regex is running, typing an asterisk will toggle the display. Alternatively, use the -nocolor parameter to switch off the color or -whitebg to switch to a suitable display for a light background. ![]() ![]() On macOS, you can use Fink for the install.ĭue to the user interface's color scheme, you will want to use txt2regex in a terminal with a dark background. Like rgxg, you will find txt2regex in the repositories of most recent distributions, such as Debian or Fedora. txt2regexĪnother command-line option, txt2regex is a shell script with keyboard-based menu control. In terms of accuracy, rgxg offers maximum precision thanks to the parameters that let you generate a regular expression that exactly matches the given pattern.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |