- implement Contains Wart for List and Option #566
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| package warts | ||
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| object Contains extends WartTraverser { | ||
| private[warts] def message: String = "Don't use List or Option `contains` method because is not typesafe" |
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actually they are type safe, just not very useful.
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it is possible to implement something like List(1).contains(true) without any warning about it
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i agree a warning would be a good thing - my issue is with the wording, because technically it is type safe: you'll never get a ClassCastException at run time, the result is correct, and there are even legitimate use cases for this behaviour. just not very many.
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I agree, can you suggest better wording for the warning?
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sorry, i'm not even sure i'd want to disable these functions without some more useful replacement - which if it existed, should probably be suggested in the message
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contains in Lists and Options is type unsafe it is possible to implement List(1).contains("1"). Use type-safe implementation for example from cats List.contains_
something like that?
| `contains` in Lists and Options is type unsafe it is possible to implement List(1).contains("1"). Use type-safe implementation for example from cats `List.contains_` | ||
| ````scala | ||
| // Won't compile: List.contains is disabled | ||
| List(1).contains(1) |
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but this is the useful case, isn't it? it might make sense to only disable them for un-related types...
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that is generally a bad idea to use native contains , my opinion is that always something like cats.contains_ should be used to be safe
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FYI 37e9823 |
Current situation:
List.containsandOption.containsoperations are not type-safe, which means it is possible to compileList(1).contains("1")this wart disables contains in List's and Options
it was also suggested here - #48