haskell-applicative-parser-2026/src/Task1.hs at main · nsu-syspro/haskell-applicative-parser-2026 · GitHub

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{-# OPTIONS_GHC -Wall #-}
-- The above pragma enables all warnings

module Task1 where

import Parser

-- | Parses natural number (including zero)
--
-- Usage example:
--
-- >>> parse nat "0"
-- Parsed 0 (Input 1 "")
-- >>> parse nat "123"
-- Parsed 123 (Input 3 "")
-- >>> parse nat "-123"
-- Failed [PosError 0 (Unexpected '-')]
-- >>> parse nat "abc"
-- Failed [PosError 0 (Unexpected 'a')]
-- >>> parse nat "123abc"
-- Parsed 123 (Input 3 "abc")
--
nat :: Parser Integer
nat = error "TODO: define nat"

-- | Parses integer number
--
-- Usage example:
--
-- >>> parse int "0"
-- Parsed 0 (Input 1 "")
-- >>> parse int "123"
-- Parsed 123 (Input 3 "")
-- >>> parse int "-123"
-- Parsed (-123) (Input 4 "")
-- >>> parse int "abc"
-- Failed [PosError 0 (Unexpected 'a')]
-- >>> parse int "123abc"
-- Parsed 123 (Input 3 "abc")
--
int :: Parser Integer
int = error "TODO: define int"