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Haskell / Values and Types

Lists

Learn Lists in Haskell through a focused explanation, a dedicated topic-specific example, an engineering boundary, and a mastery check.

10 min read • Beginner

Lists is a focused Haskell lesson inside Values and Types. The example uses the construct named in the lesson directly rather than reusing a generic placeholder.

Trace the example from its inputs through Lists and identify the behavior that would change if that construct were removed or replaced. Pay attention to the language-specific rules shown by the syntax, because neighboring lessons intentionally exercise different mechanisms.

Topic-specific example

haskell-0008-c05ad66514.hs
haskell Try It Live 
sample9 :: [Int]
sample9 = [9,10,11]
main = print (sum sample9) -- Lists
Edge case / engineering note

For Lists, test one realistic boundary: empty data, invalid input, unavailable resources, lifetime/cleanup, type constraints, or concurrency timing where applicable. A successful happy path is not enough to prove the construct is used correctly.

Content source & attribution
Original Syntaxis Content · Original Syntaxis Content

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