Can regex be nested?

Can regex be nested?

You can match nested/paired elements up to a fixed depth, where the depth is only limited by your memory, because the automaton gets very large.

How do you comment in regex?

Comments Without Free-Spacing Many flavors also allow you to add comments to your regex without using free-spacing mode. The syntax is (?# comment) where “comment” can be whatever you want, as long as it does not contain a closing parenthesis. The regex engine ignores everything after the (?#

Is long regex bad?

In General, the Longer Regex Is the Better Regex Good regular expressions are often longer than bad regular expressions because they make use of specific characters/character classes and have more structure. This causes good regular expressions to run faster as they predict their input more accurately.

How do I find commented codes?

So if you want a list of commented out code, you can:

1. right+click your project, module, subfolder, directory or file where you want to search.
2. click analyze > inspect code.
3. Click OK.

How do I get commented code from Eclipse?

From the menu, go to Window -> Preferences. In the Preferences dialog, go to General -> Editors -> Structured Text Editors -> Task Tags.

Can a regular expression check for nested structures like this?

Let me explain. @torsten-marek is right that a regular expression cannot check for nested patterns like this, BUT it is possible to define a nested regex pattern which will allow you to capture nested structures like this up to some maximum depth. I created one to capture EBNF-style comments ( try it out here ), like:

How do you parse C comments in regular expressions?

Write loads of test cases and apply your regular expression to them. Convert the automaton defined in point 1 to a regular expression, using standard techniques. A combination of the above. If you want to be sure that you’re parsing C comments, you need to confront your model with the C specification.

How to match nested parenthesis in regular expression?

Another sophisticated tool similar to sed is gema, where you will match balanced curly braces very easily with {#}. So, depending on the tools you have at your disposal your “regular expression” (in a broader sense) may be able to match nested parenthesis.

How does regex handle nested divs?

Whenever the RegEx engine matches a it pushes an empty string on the stack. On the other hand: whenever it matches a it pops the stack. Doing this – the stack would end up empty if and only if the RegEx engine discovers a correct nested construction of DIV ‘s.