Why are regular expressions bad?
The only reason why regular expressions (RegEx) is considered bad is because it might not be completely clear to the average programmer. However it generally does its job rather effectively. Take for example, when you want to check if the input is a number (both whole and/or decimal):
Is regular expression good or bad?
In General, the Longer Regex Is the Better Regex The second regular expression is indeed better than the first. Good regular expressions are often longer than bad regular expressions because they make use of specific characters/character classes and have more structure.
What is the main advantage of regular expression?
Benefits of using Regular Expression Supported by almost any language, there are only a few programming languages which do not understand regular expressions; Do more with less, keep your code cleaner; Faster validations, instead of having many IF and ELSE operators you may validate only once with a regular expression.
Should I avoid using Regex?
When Not to Use Regex Regular expressions can be a good tool, but if you try apply them to every situation, you’ll be in for a world of hurt and confusion down the line. Regex isn’t suited to parse HTML because HTML isn’t a regular language. Regex probably won’t be the tool to reach for when parsing source code.
Are regular expressions slow?
Yet matching a string with a regex can be surprisingly slow. So slow it can even stop any JS app or take 100\% of a server CPU time causing denial of service (DOS). At TextMaster we used regular expressions in an important part of our translation platform.
Why should you avoid complicated regular expressions?
Complicated regular expressions that aren’t well documented will just lead to confusion the next time you or another developer on your team comes across it. Many regex interpreters allow you to specify a flag to ignore whitespace.
Are regular expressions impossible to write or read?
So the argument that regular expressions are somehow fundamentally impossible to write or read, to me, holds no water. Like everything else, it just takes a modicum of skill. Buck up, soldier. Even Ruby code is hard to read until you learn the symbols and keywords that make up the language.
Are regular expressions good for text parsing?
Regular expressions can be a good tool, but if you try apply them to every situation, you’ll be in for a world of hurt and confusion down the line. Using them is essentially like injecting a small programming language into another programming language. This is a significant level of complexity to introduce when you’re looking for some text parsing.
Is the use of regular expressions Evil?
The first quote is too glib to be taken seriously. But this, I completely agree with. Here’s the point Jamie was trying to make: not that regular expressions are evil, per se, but that overuse of regular expressions is evil.