Using this tool, you can export this diagram (the graphical representation of the regex) as an image (SVG or PNG format) and embed it in your code documentation. You can also generate a parament link and shared it with others ( within your code, email ... ).
Let's see what is the meaning of the regex we see in the code snippet with this tool:
We can see:
Using the diagram, we can easily see that strings such as 01.03.2008 or 05-12-2015 are valid, while strings like1.3.2008, 01/03/2008 or 01-03-1593 are invalid.
In the next part we will see how to add adding comments inside regular expressions. We will also use these observations to make the regex clearer