refactor project
This commit is contained in:
parent
633fbf566c
commit
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4 changed files with 190 additions and 164 deletions
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@ -62,13 +62,15 @@ library
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exposed-modules: Lib
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exposed-modules: Lib
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-- Modules included in this library but not exported.
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-- Modules included in this library but not exported.
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-- other-modules:
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other-modules:
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Lexer
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-- LANGUAGE extensions used by modules in this package.
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-- LANGUAGE extensions used by modules in this package.
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-- other-extensions:
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-- other-extensions:
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-- Other library packages from which modules are imported.
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-- Other library packages from which modules are imported.
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build-depends: base ^>=4.18.2.1
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build-depends:
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base ^>=4.18.2.1
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-- Directories containing source files.
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-- Directories containing source files.
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hs-source-dirs: src
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hs-source-dirs: src
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@ -125,4 +127,5 @@ test-suite lisp-interpreter-test
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-- Test dependencies.
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-- Test dependencies.
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build-depends:
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build-depends:
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base ^>=4.18.2.1,
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base ^>=4.18.2.1,
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HUnit,
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lisp-interpreter
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lisp-interpreter
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157
src/Lexer.hs
Normal file
157
src/Lexer.hs
Normal file
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@ -0,0 +1,157 @@
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module Lexer(
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Token (..),
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lexStr
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)where
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import Data.Char
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data Token = TokLPar
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| TokRPar
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| TokQuote
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| TokNumber Double
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| TokStr String
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| TokCharacter Char
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| TokSymbol String
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| TokErr String
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deriving Eq
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data StrState = StrStart
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| StrInside
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| StrEscape
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identifyString :: String -> StrState -> (String, Maybe String)
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identifyString ('"':xs) StrStart = identifyString xs StrInside
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identifyString xs StrStart = (xs, Nothing) -- will never occur
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identifyString "" _ = ("", Nothing) -- early end of file
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identifyString ('\\':xs) StrInside = identifyString xs StrEscape
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identifyString ('"':xs) StrInside = (xs, Just "")
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identifyString ('n':xs) StrEscape = case identifyString xs StrInside
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of (ys, Just b) -> (ys, Just ('\n':b))
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y -> y
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identifyString ('\\':xs) StrEscape = case identifyString xs StrInside
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of (ys, Just b) -> (ys, Just ('\\':b))
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y -> y
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identifyString ('/':xs) StrEscape = case identifyString xs StrInside
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of (ys, Just b) -> (ys, Just ('/':b))
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y -> y
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identifyString ('"':xs) StrEscape = case identifyString xs StrInside
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of (ys, Just b) -> (ys, Just ('"':b))
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y -> y
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identifyString ('b':xs) StrEscape = case identifyString xs StrInside
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of (ys, Just b) -> (ys, Just ('\b':b))
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y -> y
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identifyString ('f':xs) StrEscape = case identifyString xs StrInside
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of (ys, Just b) -> (ys, Just ('\f':b))
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y -> y
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identifyString ('r':xs) StrEscape = case identifyString xs StrInside
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of (ys, Just b) -> (ys, Just ('\r':b))
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y -> y
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identifyString ('t':xs) StrEscape = case identifyString xs StrInside
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of (ys, Just b) -> (ys, Just ('\t':b))
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y -> y
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identifyString ('u':w:x:y:z:xs) StrEscape | isHexDigit w &&
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isHexDigit x &&
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isHexDigit y &&
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isHexDigit z =
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case identifyString xs StrInside
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of (ys, Just b) -> (ys, Just (chr (read ('0':'x':w:x:y:z:"")):b))
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a -> a
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identifyString (x:xs) StrEscape = (x:xs, Nothing)
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identifyString (x:xs) StrInside = case identifyString xs StrInside
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of (ys, Nothing) -> (ys, Nothing)
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(ys, Just b) -> (ys, Just (x:b))
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data NumState = NumStart
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| NumNeg
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| NumIntegralComponent
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| NumFractionalComponent
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| NumExponentialComponent
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identifyNum :: String -> NumState -> (String, Maybe String)
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identifyNum "" NumStart = ("", Nothing)
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identifyNum ('-':xs) NumStart = identifyNum xs NumNeg
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identifyNum ('0':'.':x:xs) NumStart | isDigit x = case identifyNum (x:xs) NumFractionalComponent
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of (ys, Just zs) -> (ys, Just ('0':'.':zs))
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y -> y
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| otherwise = (x:xs, Nothing)
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identifyNum (x:xs) NumStart | x == '0' = (x:xs, Nothing)
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| isDigit x = identifyNum (x:xs) NumIntegralComponent
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| otherwise = (x:xs, Nothing)
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identifyNum "" NumNeg = ("", Nothing)
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identifyNum ('0':'.':x:xs) NumNeg | isDigit x = case identifyNum (x:xs) NumFractionalComponent
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of (ys, Just zs) -> (ys, Just ('-':'0':'.':zs))
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y -> y
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identifyNum (x:xs) NumNeg | x == '0' = (x:xs, Nothing)
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| isDigit x = case identifyNum (x:xs) NumIntegralComponent
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of (ys, Just zs) -> (ys, Just ('-':zs))
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y -> y
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| otherwise = (x:xs, Nothing)
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identifyNum ('.':x:xs) NumIntegralComponent | isDigit x = case identifyNum (x:xs) NumFractionalComponent
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of (ys, Just zs) -> (ys, Just ('.':zs))
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y -> y
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| otherwise = ('.':x:xs, Just "")
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identifyNum (w:x:y:xs) NumIntegralComponent | (w == 'e' || w == 'E') &&
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(x == '+' || x == '-') &&
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isDigit y =
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case identifyNum (y:xs) NumExponentialComponent
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of (ys, Just zs) -> (ys, Just (w:x:zs))
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z -> z
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| (w == 'e' || w == 'E') &&
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isDigit x =
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case identifyNum (x:y:xs) NumExponentialComponent
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of (ys, Just zs) -> (ys, Just (w:zs))
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z -> z
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identifyNum (x:y:"") NumIntegralComponent | (x == 'e' || x == 'E') &&
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isDigit y = ("", Just (x:y:""))
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| isDigit x && isDigit y = ("", Just (x:y:""))
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| isDigit x = (y:"", Just (x:""))
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| otherwise = (x:y:"", Just "")
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identifyNum (x:xs) NumIntegralComponent | isDigit x = case identifyNum xs NumIntegralComponent
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of (ys, Just zs) -> (ys, Just (x:zs))
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y -> y
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| otherwise = (x:xs, Just "")
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identifyNum (w:x:y:xs) NumFractionalComponent | (w == 'e' || w == 'E') &&
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(x == '+' || x == '-') &&
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isDigit y =
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case identifyNum (y:xs) NumExponentialComponent
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of (ys, Just zs) -> (ys, Just (w:x:zs))
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z -> z
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| (w == 'e' || w == 'E') &&
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isDigit x =
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case identifyNum (x:y:xs) NumExponentialComponent
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of (ys, Just zs) -> (ys, Just (w:zs))
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z -> z
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identifyNum (x:y:"") NumFractionalComponent | (x == 'e' || x == 'E') &&
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isDigit y = ("", Just (x:y:""))
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| isDigit x && isDigit y = ("", Just (x:y:""))
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| isDigit x = (y:"", Just (x:""))
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| otherwise = (x:y:"", Just "")
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identifyNum (x:xs) NumFractionalComponent | isDigit x = case identifyNum xs NumFractionalComponent
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of (ys, Just zs) -> (ys, Just (x:zs))
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y -> y
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| otherwise = (x:xs, Just "")
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identifyNum (x:xs) NumExponentialComponent | isDigit x = case identifyNum xs NumExponentialComponent
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of (ys, Just zs) -> (ys, Just (x:zs))
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y -> y
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| otherwise = (x:xs, Just "")
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identifyNum [] _ = ("", Just "")
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lexStr :: String -> [Token]
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lexStr "" = []
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lexStr ('(':xs) = TokLPar : lexStr xs
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lexStr (')':xs) = TokRPar : lexStr xs
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lexStr ('"':xs) = case identifyString ('"':xs) StrStart
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of (ys, Nothing) -> TokErr "End of file reached before matching \"" :lexStr ys
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(ys, Just b) -> TokStr b:lexStr ys
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lexStr ('\'':"") = [TokErr "End of file reached before matching '"]
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lexStr ('\'':'(':xs) = TokQuote : lexStr ('(':xs)
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lexStr ('\'':_:"") = [TokErr "End of file reached before matching '"]
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lexStr ('\'':x:'\'':xs) = TokCharacter x : lexStr xs
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lexStr (' ':xs) = lexStr xs
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lexStr ('\t':xs) = lexStr xs
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lexStr ('\n':xs) = lexStr xs
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lexStr ('\r':xs) = lexStr xs
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lexStr (x:xs) | isDigit x || x == '-' = case identifyNum (x:xs) NumStart
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of (ys, Nothing) -> TokErr "Failed to parse number" : lexStr ys
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(ys, Just b) -> TokNumber (read b) : lexStr ys
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lexStr _ = []
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161
src/Lib.hs
161
src/Lib.hs
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@ -1,157 +1,10 @@
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module Lib where
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module Lib(
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Lexer.Token(..),
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Lexer.lexStr,
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someFunc
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)where
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import Data.Char
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import Lexer
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someFunc :: IO ()
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someFunc :: IO ()
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someFunc = putStrLn "someFunc"
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someFunc = putStrLn "Hello, world"
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data Token = LPar
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| RPar
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| Quote
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| Number Double
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| Str String
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| Character Char
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| Symbol String
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| Err String
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deriving Eq
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data StrState = StrStart
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| StrInside
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| StrEscape
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identifyString :: String -> StrState -> (String, Maybe String)
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identifyString ('"':xs) StrStart = identifyString xs StrInside
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identifyString xs StrStart = (xs, Nothing) -- will never occur
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identifyString "" _ = ("", Nothing) -- early end of file
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identifyString ('\\':xs) StrInside = identifyString xs StrEscape
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identifyString ('"':xs) StrInside = (xs, Just "")
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identifyString ('n':xs) StrEscape = case identifyString xs StrInside
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of (ys, Just b) -> (ys, Just ('\n':b))
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y -> y
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identifyString ('\\':xs) StrEscape = case identifyString xs StrInside
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of (ys, Just b) -> (ys, Just ('\\':b))
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y -> y
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identifyString ('/':xs) StrEscape = case identifyString xs StrInside
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of (ys, Just b) -> (ys, Just ('/':b))
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y -> y
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identifyString ('"':xs) StrEscape = case identifyString xs StrInside
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of (ys, Just b) -> (ys, Just ('"':b))
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y -> y
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identifyString ('b':xs) StrEscape = case identifyString xs StrInside
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of (ys, Just b) -> (ys, Just ('\b':b))
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y -> y
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identifyString ('f':xs) StrEscape = case identifyString xs StrInside
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of (ys, Just b) -> (ys, Just ('\f':b))
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y -> y
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identifyString ('r':xs) StrEscape = case identifyString xs StrInside
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of (ys, Just b) -> (ys, Just ('\r':b))
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y -> y
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identifyString ('t':xs) StrEscape = case identifyString xs StrInside
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of (ys, Just b) -> (ys, Just ('\t':b))
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y -> y
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identifyString ('u':w:x:y:z:xs) StrEscape | isHexDigit w &&
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isHexDigit x &&
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isHexDigit y &&
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isHexDigit z =
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case identifyString xs StrInside
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of (ys, Just b) -> (ys, Just (chr (read ('0':'x':w:x:y:z:"")):b))
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a -> a
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identifyString (x:xs) StrEscape = (x:xs, Nothing)
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identifyString (x:xs) StrInside = case identifyString xs StrInside
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of (ys, Nothing) -> (ys, Nothing)
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(ys, Just b) -> (ys, Just (x:b))
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data NumState = NumStart
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| NumNeg
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| NumIntegralComponent
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| NumFractionalComponent
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| NumExponentialComponent
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identifyNum :: String -> NumState -> (String, Maybe String)
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identifyNum "" NumStart = ("", Nothing)
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identifyNum ('-':xs) NumStart = identifyNum xs NumNeg
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identifyNum ('0':'.':x:xs) NumStart | isDigit x = case identifyNum (x:xs) NumFractionalComponent
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of (ys, Just zs) -> (ys, Just ('0':'.':zs))
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y -> y
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| otherwise = (x:xs, Nothing)
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identifyNum (x:xs) NumStart | x == '0' = (x:xs, Nothing)
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| isDigit x = identifyNum (x:xs) NumIntegralComponent
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| otherwise = (x:xs, Nothing)
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identifyNum "" NumNeg = ("", Nothing)
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identifyNum ('0':'.':x:xs) NumNeg | isDigit x = case identifyNum (x:xs) NumFractionalComponent
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of (ys, Just zs) -> (ys, Just ('-':'0':'.':zs))
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y -> y
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identifyNum (x:xs) NumNeg | x == '0' = (x:xs, Nothing)
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| isDigit x = case identifyNum (x:xs) NumIntegralComponent
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of (ys, Just zs) -> (ys, Just ('-':zs))
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y -> y
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| otherwise = (x:xs, Nothing)
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identifyNum ('.':x:xs) NumIntegralComponent | isDigit x = case identifyNum (x:xs) NumFractionalComponent
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of (ys, Just zs) -> (ys, Just ('.':zs))
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y -> y
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| otherwise = ('.':x:xs, Just "")
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identifyNum (w:x:y:xs) NumIntegralComponent | (w == 'e' || w == 'E') &&
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(x == '+' || x == '-') &&
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isDigit y =
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case identifyNum (y:xs) NumExponentialComponent
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of (ys, Just zs) -> (ys, Just (w:x:zs))
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z -> z
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| (w == 'e' || w == 'E') &&
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isDigit x =
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case identifyNum (x:y:xs) NumExponentialComponent
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of (ys, Just zs) -> (ys, Just (w:zs))
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z -> z
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identifyNum (x:y:"") NumIntegralComponent | (x == 'e' || x == 'E') &&
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isDigit y = ("", Just (x:y:""))
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| isDigit x && isDigit y = ("", Just (x:y:""))
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| isDigit x = (y:"", Just (x:""))
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| otherwise = (x:y:"", Just "")
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identifyNum (x:xs) NumIntegralComponent | isDigit x = case identifyNum xs NumIntegralComponent
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of (ys, Just zs) -> (ys, Just (x:zs))
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y -> y
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| otherwise = (x:xs, Just "")
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identifyNum (w:x:y:xs) NumFractionalComponent | (w == 'e' || w == 'E') &&
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(x == '+' || x == '-') &&
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isDigit y =
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case identifyNum (y:xs) NumExponentialComponent
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of (ys, Just zs) -> (ys, Just (w:x:zs))
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z -> z
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| (w == 'e' || w == 'E') &&
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isDigit x =
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case identifyNum (x:y:xs) NumExponentialComponent
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of (ys, Just zs) -> (ys, Just (w:zs))
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z -> z
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identifyNum (x:y:"") NumFractionalComponent | (x == 'e' || x == 'E') &&
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isDigit y = ("", Just (x:y:""))
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| isDigit x && isDigit y = ("", Just (x:y:""))
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| isDigit x = (y:"", Just (x:""))
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| otherwise = (x:y:"", Just "")
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identifyNum (x:xs) NumFractionalComponent | isDigit x = case identifyNum xs NumFractionalComponent
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of (ys, Just zs) -> (ys, Just (x:zs))
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y -> y
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| otherwise = (x:xs, Just "")
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identifyNum (x:xs) NumExponentialComponent | isDigit x = case identifyNum xs NumExponentialComponent
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of (ys, Just zs) -> (ys, Just (x:zs))
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y -> y
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| otherwise = (x:xs, Just "")
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|
||||||
identifyNum [] _ = ("", Just "")
|
|
||||||
|
|
||||||
lexStr :: String -> [Token]
|
|
||||||
lexStr "" = []
|
|
||||||
lexStr ('(':xs) = LPar : lexStr xs
|
|
||||||
lexStr (')':xs) = RPar : lexStr xs
|
|
||||||
lexStr ('"':xs) = case identifyString ('"':xs) StrStart
|
|
||||||
of (ys, Nothing) -> Err "End of file reached before matching \"" :lexStr ys
|
|
||||||
(ys, Just b) -> Str b:lexStr ys
|
|
||||||
lexStr ('\'':"") = [Err "End of file reached before matching '"]
|
|
||||||
lexStr ('\'':'(':xs) = Quote : lexStr ('(':xs)
|
|
||||||
lexStr ('\'':_:"") = [Err "End of file reached before matching '"]
|
|
||||||
lexStr ('\'':x:'\'':xs) = Character x : lexStr xs
|
|
||||||
lexStr (' ':xs) = lexStr xs
|
|
||||||
lexStr ('\t':xs) = lexStr xs
|
|
||||||
lexStr ('\n':xs) = lexStr xs
|
|
||||||
lexStr ('\r':xs) = lexStr xs
|
|
||||||
lexStr (x:xs) | isDigit x || x == '-' = case identifyNum (x:xs) NumStart
|
|
||||||
of (ys, Nothing) -> Err "Failed to parse number" : lexStr ys
|
|
||||||
(ys, Just b) -> Number (read b) : lexStr ys
|
|
||||||
lexStr _ = []
|
|
||||||
|
|
|
||||||
29
test/Main.hs
29
test/Main.hs
|
|
@ -1,20 +1,33 @@
|
||||||
module Main (main) where
|
module Main (main) where
|
||||||
|
|
||||||
import System.Exit (exitFailure)
|
import System.Exit (exitFailure, exitSuccess)
|
||||||
import Control.Monad
|
import Control.Monad
|
||||||
|
|
||||||
|
import Test.HUnit
|
||||||
|
|
||||||
import Lib
|
import Lib
|
||||||
|
|
||||||
|
test1 :: Test
|
||||||
|
test1 = TestCase (assertEqual "2==2" (2.0 :: Double) (2 :: Double))
|
||||||
|
|
||||||
|
tests :: Test
|
||||||
|
tests = TestList [
|
||||||
|
TestLabel "test 1" test1
|
||||||
|
]
|
||||||
|
|
||||||
main :: IO ()
|
main :: IO ()
|
||||||
main = do
|
main = do
|
||||||
when (lexStr "'('a' -1.01e12 \r \"\\uabcdasdf\\b\\f\\r\\n\\t\\\\\\/\" )\"asdf"
|
when (lexStr "'('a' -1.01e12 \r \"\\uabcdasdf\\b\\f\\r\\n\\t\\\\\\/\" )\"asdf"
|
||||||
/= [
|
/= [
|
||||||
Quote,
|
Lib.TokQuote,
|
||||||
LPar,
|
Lib.TokLPar,
|
||||||
Character 'a',
|
Lib.TokCharacter 'a',
|
||||||
Number (-1.01e12),
|
Lib.TokNumber (-1.01e12),
|
||||||
Str "\43981asdf\b\f\r\n\t\\/",
|
Lib.TokStr "\43981asdf\b\f\r\n\t\\/",
|
||||||
RPar,
|
Lib.TokRPar,
|
||||||
Err "End of file reached before matching \""
|
Lib.TokErr "End of file reached before matching \""
|
||||||
])
|
])
|
||||||
exitFailure
|
exitFailure
|
||||||
|
c <- runTestTT tests
|
||||||
|
putStrLn (showCounts c)
|
||||||
|
exitSuccess
|
||||||
|
|
|
||||||
Loading…
Add table
Reference in a new issue