12 lines
367 B
Markdown
12 lines
367 B
Markdown
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Haskell Functors for the programmer
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`Functor` is a type class used for types that can be mapped over.
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- Containers: `[]`, Trees, Map, HashMap...
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- "Feature Type":
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- `Maybe a`: help to handle absence of `a`.
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Ex: `safeDiv x 0 ⇒ Nothing`
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- `Either String a`: help to handle errors
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Ex: `reportDiv x 0 ⇒ Left "Division by 0!"`
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