Avoid parse error occurred when the field name generated by TH matches any of Haskell keywords#1476
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parsonsmatt
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Thanks for writing this up! One minor performance quibble.
At a future point, it would be nice to customize this behavior.
Since anyone writing type as a field name currently will receive GHC error, I think we can safely call this a bugfix. Mind doing a patch version bump and adding a changelog notice?
persistent/Database/Persist/TH.hs
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| avoidKeyword name = if name `elem` keywords then name ++ "_" else name | ||
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| keywords :: [Text] | ||
| keywords = | ||
| ["case","class","data","default","deriving","do","else" | ||
| ,"if","import","in","infix","infixl","infixr","instance","let","module" | ||
| ,"newtype","of","then","type","where","_" | ||
| ,"foreign" | ||
| ] |
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Lots of list lookups like this is pretty inefficient - would prefer to see a Set lookup
| avoidKeyword name = if name `elem` keywords then name ++ "_" else name | |
| keywords :: [Text] | |
| keywords = | |
| ["case","class","data","default","deriving","do","else" | |
| ,"if","import","in","infix","infixl","infixr","instance","let","module" | |
| ,"newtype","of","then","type","where","_" | |
| ,"foreign" | |
| ] | |
| avoidKeyword name = if name `Set.member` haskellKeywords then name ++ "_" else name | |
| haskellKeywords :: Set Text | |
| haskellKeywords = Set.fromList | |
| ["case","class","data","default","deriving","do","else" | |
| ,"if","import","in","infix","infixl","infixr","instance","let","module" | |
| ,"newtype","of","then","type","where","_" | |
| ,"foreign" | |
| ] |
Floating it to the top-level ensures we aren't constructing the Set for each call to mkRecordName, though I would guess GHC is capable of performing that optimization on it's own
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Thank you for your review, I changed the suggested part and added a notice to bump up a patch version in ChangeLog.
parsonsmatt
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awesome, thanks! I'll release this today.
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To avoid the problem that GHC fails compiling due to parse error when the field name generated by Template Haskell matches any of Haskell keywords, this PR fixes
mkRecordNameto suffix_if the field name matches any of keywords.Before submitting your PR, check that you've:
@sincedeclarations to the Haddockstylish-haskellon any changed files..editorconfigfile for details)After submitting your PR:
(unreleased)on the Changelog