Does the thought of a confusing regular expression send chills down your back? Don't worry; you're in the majority. But, luckily, the truth is that the trick to understanding regular expressions simply boils down to basic memorization. It's not that tough, once you know what you're looking for.
A Birds-Eye View
To begin this series, let's zoom out for a few moments, and review what regular expressions look like, how we can write our own, and what that might look like in our PHP code.
Alternation
Let's slow down a bit, and focus on a silly example, that will allow us to review such topics as alternation, optional sequences, and non-capturing groups.
Character Sets
Character sets allow us to match any one token, out of a group of characters. As you'll find, this can be incredibly powerful. Let me show you.
Greediness
Using a practical, real world example, let's review regular expression greediness in this episode.
Lookaheads and Lookbehinds
Often, you'll find yourself in the position of needing to match a set of characters only if they are proceeded or preceded by another sequence.
PHP's Regular Expressions Support
So far, we've mostly been focusing on the regular expression syntax. But, now, let's switch over to PHP and learn about the various regex-specific functions that are available to us.
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