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awalterschulze/medium-derivative-of-a-regex-derive-answer-2.hs Secret

Created August 31, 2022 09:02
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medium-derivative-of-a-regex-derive-answer-2.hs
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medium-derivative-of-a-regex-derive-answer-2.hs
derive "b*(b|c)" 'b'
= (derive "b*" 'b') `concat` "b|c"
`or`
(derive "b|c" 'b')
= (derive "b" 'b') `concat` "b*" `concat` "b|c"
`or`
(derive "b" 'b') `or` (derive "c" 'b')
= "ε" `concat` "b*" `concat` "b|c"
`or`
"ε" `or` "∅"
= "(εb*(b|c))|(ε|∅)"
= "b*(b|c)|ε"
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