11 lines
384 B
Markdown
11 lines
384 B
Markdown
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Klesli composition
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Now the composition works as expected. In Haskell ◎ is `<=<` in `Control.Monad`.
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`g <=< f = \x -> join ((fmap g) (f x))`
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<pre class="haskell"><code>f x = [x] ⇒ f 1 = [1] ⇒ (f <=< f) 1 = [1] ✓
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g x = [x+1] ⇒ g 1 = [2] ⇒ (g <=< g) 1 = [3] ✓
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h x = [x+1,x*3] ⇒ h 1 = [2,3] ⇒ (h <=< h) 1 = [3,6,4,9] ✓</code></pre>
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