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I'm trying to update the Real World Haskell book
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Some Problems in Chapter 14 #38

Open pdcxs opened 3 years ago

pdcxs commented 3 years ago

I follow the codes in chapter 14 and find some little problems.

  1. charClass_wordy defined but not used, I think maybe the charClass function should be modified as following:

    charClass (']':cs) = (']':) <$> globToRegex' cs
charClass (c:cs) = (c:) <$> charClass_wordy cs

  2. According to monad fail, from GHC 8.8+, the fail function will not be supported. I suggest change the fail function to error or other implementation.

  3. charClass_wordy also lacks a matching form, which should be added as follows:

    charClassWordy "" = 
error "No more input"