What are some advanced pattern matching techniques in Haskell?

What are some advanced pattern matching techniques in Haskell?

In Haskell, advanced pattern matching techniques include using guards, as-patterns, and view patterns. Would you like to explore one of these?

Can you explain how guards work in pattern matching?

Sure! Guards allow you to specify additional conditions for a pattern match. They are used with the '|' symbol to create more complex matching scenarios.

Could you give me an example of using guards?

Absolutely! Here's a simple example: f x | x < 0 = 'negative' | x == 0 = 'zero' | otherwise = 'positive'. This function classifies a number based on its value.

What are as-patterns and how do they differ from regular patterns?

As-patterns allow you to match a value while also giving it a name. For example, in let Just x = y in ..., you can use 'x' in the expression while still matching 'y'.