Object objects in javascript can be said to account for half of the country, there is a saying called: "everything is Object", although not accurate, but also a clear expression of the Object in Js is important

Looking at a re, it's hard to intuitively know what it does; Writing a re makes it hard to visualize how the machine will handle it. Therefore, unexpected or unexpected problems often arise. Today we're going to talk about something that seriously affects performance, which I call the Backtracking trap or Catastrophic Backtracking.

The fourth installment of the KOA source code reading deals with providing file data to the interface requester. Dealing with static files is a tedious task, because static files come from the server, and you can't give away all permissions to the interface to read them. The verification of various paths and the matching of permissions are all things that need to be taken into account. Koa-send and KOA-static help us deal with these things...

-- -- -- -- -- -- -- -- -- -- - search keyword | | regular expressions, highlighting the replace application -- -- -- -- -- -- -- -- -- -- -- -- -- --

This time share a simple path replacement tool. The function is very simple, the key is to master: recursive traverse folder directory regular replacement target content, decompression upload file, return the updated compressed file

The input box allows only positive and negative integers /(? < =.) \-|[^\d\-]/g

Write at the beginning: I plan to write a Kotlin series of tutorials, one is to make my own memory and understanding more profound, two is to share with the students who also want to learn Kotlin. The knowledge points in this series of articles will be written in order from the book "Kotlin In Action". While displaying the knowledge points in the book, I will also add corresponding Java code for comparative learning and better understanding. In the last chapter, I...

I searched many posts about Unicode, but found that the "[" is the symbol of the metachild table, which needs to be escaped

This is my 22nd day of the August Text Challenge. Regular expressions are patterns that match either characters or positions. Please remember this sentence. However, most people do not attach so much importance to the matching position when they learn regularity. This chapter is about positivity

The second point is easier to solve, and can be avoided by using lazy matching within a pair of tags. For the first and third points, however, we need to borrow the regular backtrace reference. Backtrace reference refers to the second half of the pattern referring to the subexpression defined in the first half, and can only be used to refer to the subexpression in the pattern (that is, the part enclosed by metacharacters (and)). Easy to understand, can think of backtracking reference...