11 lines
416 B
Markdown
11 lines
416 B
Markdown
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Necessary laws
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For ◎ to work like composition, we need join to hold the following properties:
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- `join (join (F (F (F a))))=join (F (join (F (F a))))`
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- abusing notations denoting `join` by ⊙; this is equivalent to
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<span class="yellow">`(F ⊙ F) ⊙ F = F ⊙ (F ⊙ F)`</span>
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- There exists `η :: a -> F a` s.t.
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<span class="yellow">`η⊙F=F=F⊙η`</span>
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