Tool to analyze a regular expression and understand its interpretation mechanism and extracting internal properties through the analyzer.
Regular Expression Analyzer - dCode
Tag(s) : Data Processing
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Regular Expression Analyzer
Regular Expression Analyzer
Answers to Questions (FAQ)
What is a syntax diagram for a regular expression analyzer? (Definition)
The analysis of a regular expression consists in breaking down each element of this one in order to propose a visualization of it a little more intuitive called syntax diagram (often called railroad diagram).
How to analyze a regular expression?
The software of regex analysis decomposes a regular expression in order to find each component (characters, pattern, matches) and describe its meaning. The analysis is based on a cut of the pattern matching expression.
Example: /\d{2,5}/ correspond to \d (digit) {2,5} between 2 and 5 times.
dCode uses the work of takayoshiotake (MIT License) here
How to calculate the length of a string catchable by regex?
The script gets minimum and maximum sizes of each element of the expression and calculates the total.
Example: (ab|cde){2,3} has for minimum length 4 (case abab) and maximum 9 (case cdecdecde)
Example: a+ has for minimal length 1 (case a) and maximal infinite (case aaaaa…a)
How to test a regexp?
Currently dCode can do regular expression searches but no real test feature. To test a regular expression, dCode's advice is to use the site Regex101 here with a Javascript inerface that allow seeing instantly (by underlined characters) detected items or captured in the regular expression.
Source code
dCode retains ownership of the "Regular Expression Analyzer" source code. Any algorithm for the "Regular Expression Analyzer" algorithm, applet or snippet or script (converter, solver, encryption / decryption, encoding / decoding, ciphering / deciphering, breaker, translator), or any "Regular Expression Analyzer" functions (calculate, convert, solve, decrypt / encrypt, decipher / cipher, decode / encode, translate) written in any informatic language (Python, Java, PHP, C#, Javascript, Matlab, etc.) or any database download or API access for "Regular Expression Analyzer" or any other element are not public (except explicit open source licence). Same with the download for offline use on PC, mobile, tablet, iPhone or Android app.
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