21 lines
717 B
TeX
21 lines
717 B
TeX
So why did we just bother so long with explaining currying? It's because it's very important for \emph{function composition}. Which again is also one of the fundamental concepts of functional programming.
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\vspace{\baselineskip}
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\\
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From maths we already know that:\\
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$(g \circ f)(x) = g(f(x))$
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\vspace{\baselineskip}
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\\
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\pause
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And that's basically it. We do the same in haskell, it looks like this:
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\begin{haskellcode}
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composedFunction x = (f . g) x
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-- same as above... everything on the right side of $
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-- is evaluated first
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composedFunction x = f . g $ x
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-- and same again, remember that 'f x ='
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-- is just syntax sugar
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-- omitting the x here is also called eta reduction
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composedFunction = f . g
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\end{haskellcode} |