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copied!<p>Generalized versions of <code>oneOf</code>, <code>noneOf</code>, and <code>anyChar</code> can be built out of a generalized <code>satisfy</code>, easily enough:</p> <pre><code>oneOfT :: (Eq t, Show t, Stream s m t) => [t] -> ParsecT s u m t oneOfT ts = satisfyT (`elem` ts) noneOfT :: (Eq t, Show t, Stream s m t) => [t] -> ParsecT s u m t noneOfT ts = satisfyT (not . (`elem` ts)) anyT :: (Show t, Stream s m t) => ParsecT s u m t anyT = satisfyT (const True) satisfyT :: (Show t, Stream s m t) => (t -> Bool) -> ParsecT s u m t satisfyT p = tokenPrim showTok nextPos testTok where showTok t = show t testTok t = if p t then Just t else Nothing nextPos p t s = -- however you update position for your token stream </code></pre> <p>It might seem that the generalization of these seems missing, but you'll notice that these generalizations here make certain assumptions about the type <code>t</code> that may not be true for someone's token type. It is assumed to be an instance of <code>Show</code> and <code>Eq</code>, yet I can imagine token types for which they are displayed some other way than <code>show</code>, and that membership in a class of tokens might be achieved via some method other than <code>==</code> and <code>elem</code>.</p> <p>Lastly, once your token type is no longer a <code>Char</code>, how you choose to represent position, and thus updated it, is highly dependent on your representation of tokens and streams.</p> <p>Hence, I can see why a more generalized form doesn't exist.</p>

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