X-Git-Url: https://git.martlubbers.net/?a=blobdiff_plain;f=lex.icl;h=2eeb6007c23d2b4188797f98b68937d25c1ec0a4;hb=889d4798a0da64d76422da98378f5e5c35f0bf32;hp=f050062d7f172760b708a867a469d06cba3dc75c;hpb=19c5f39c61f1692641570dc3cf13360e7dff5cdf;p=cc1516.git diff --git a/lex.icl b/lex.icl index f050062..2eeb600 100644 --- a/lex.icl +++ b/lex.icl @@ -1,3 +1,158 @@ -module lex +implementation module lex -Start = "Hello World!\n" +from Text import class Text, instance Text String +import Control.Monad +import Data.Either +import Data.Functor +import Data.List +import StdString +import StdBool +import StdFile +import System.CommandLine +import qualified Text + +Start :: *World -> *World +Start w +# (out, w) = stdio w +# (toparse, out) = readEntireFile out +# (_, w) = fclose (out <<< "\n" <<< toString (lexer toparse)) w += w + +readEntireFile :: *File -> *([Char], *File) +readEntireFile f +# (b, c, f) = freadc f +| not b = ([], f) +# (cs, f) = readEntireFile f += ([c:cs], f) + +lexer :: [Char] -> LexerOutput +lexer [] = Right [] +lexer x = case lex x of + (Right t, rest) = lexer rest >>= \ts.Right [t:ts] + (Left e, _) = Left e + +untilNext :: [Char] -> [Char] +untilNext [] = [] +untilNext ['*':'/':rest] = rest +untilNext [x:rest] = untilNext rest + +lex :: [Char] -> (Either String Token, [Char]) +lex [] = (Right EndOfFileToken, []) +//Comments +lex ['/':'/':rest] = lex (tl (dropWhile ((<>) '\n') rest)) +lex ['/':'*':rest] = lex (untilNext rest) +//Keyword tokens +lex ['v':'a':'r':rest] = (Right VarToken, rest) +lex ['V':'o':'i':'d':rest] = (Right VoidToken, rest) +lex ['r':'e':'t':'u':'r':'n':rest] = (Right ReturnToken, rest) +lex ['i':'f':rest] = (Right IfToken, rest) +lex ['e':'l':'s':'e':rest] = (Right ElseToken, rest) +lex ['w':'h':'i':'l':'e':rest] = (Right WhileToken, rest) +lex ['T':'r':'u':'e':rest] = (Right TrueToken, rest) +lex ['F':'a':'l':'s':'e':rest] = (Right FalseToken, rest) +lex ['I':'n':'t':rest] = (Right IntTypeToken, rest) +lex ['C':'h':'a':'r':rest] = (Right CharTypeToken, rest) +lex ['B':'o':'o':'l':rest] = (Right BoolTypeToken, rest) +//Two character tokens +lex [':':':':rest] = (Right DoubleColonToken, rest) +lex ['!':'=':rest] = (Right NotEqualToken, rest) +lex ['<':'=':rest] = (Right LesserEqToken, rest) +lex ['>':'=':rest] = (Right GreaterEqToken, rest) +lex ['=':'=':rest] = (Right EqualsToken, rest) +lex ['&':'&':rest] = (Right AmpersandsToken, rest) +lex ['|':'|':rest] = (Right PipesToken, rest) +lex ['-':'>':rest] = (Right ArrowToken, rest) +//One character tokens +lex ['(':rest] = (Right BraceOpenToken, rest) +lex [')':rest] = (Right BraceCloseToken, rest) +lex ['{':rest] = (Right CBraceOpenToken, rest) +lex ['}':rest] = (Right CBraceCloseToken, rest) +lex ['[':rest] = (Right SquareOpenToken, rest) +lex [']':rest] = (Right SquareCloseToken, rest) +lex [',':rest] = (Right CommaToken, rest) +lex [':':rest] = (Right ColonToken, rest) +lex [';':rest] = (Right SColonToken, rest) +lex ['.':rest] = (Right DotToken, rest) +lex ['+':rest] = (Right PlusToken, rest) +lex ['-':rest] = (Right DashToken, rest) +lex ['*':rest] = (Right StarToken, rest) +lex ['/':rest] = (Right SlashToken, rest) +lex ['%':rest] = (Right PercentToken, rest) +lex ['=':rest] = (Right AssignmentToken, rest) +lex ['<':rest] = (Right LesserToken, rest) +lex ['>':rest] = (Right BiggerToken, rest) +lex ['!':rest] = (Right ExclamationToken, rest) +//Value tokens +lex ['\'':x:'\'':rest] = (Right (CharToken x), rest) +lex ['\'':'\\':x:'\'':rest] = case x of + 'a' = (Right (CharToken (toChar 7)), rest) //Alarm + 'b' = (Right (CharToken '\b'), rest) //Backspace + 'f' = (Right (CharToken '\f'), rest) //Formfeed + 'n' = (Right (CharToken '\n'), rest) //Newline + 'r' = (Right (CharToken '\r'), rest) //Carriage Return + 't' = (Right (CharToken '\t'), rest) //Horizontal tab + 'v' = (Right (CharToken '\v'), rest) //Vertical tab + _ = (Left ("Unknown escape: \\" +++ toString x), []) +lex [x:xs] +| isSpace x = lex xs +| isDigit x = let (is, rest) = span isDigit xs in + (Right (NumberToken [x:is]), rest) +| isAlpha x = let (is, rest) = span (\c.isAlphanum c || c == '_') xs in + (Right (IdentToken [x:is]), rest) +| otherwise = (Left ("Unexpected character: " +++ toString x), []) + +instance toString LexerOutput where + toString (Left l) = "Error: " +++ l + toString (Right x) = 'Text'.concat (print 0 x) + +tab :: Int -> [String] +tab i = replicate i "\t" + +print :: Int [Token] -> [String] +print _ [] = [] +print i [(IdentToken l):rest] = [toString l:print i rest] +print i [(NumberToken j):rest] = [toString j:print i rest] +print i [(CharToken c):rest] = ["'":toString c:"'":print i rest] +print i [VarToken:rest] = ["var ":print i rest] +print i [ReturnToken:rest] = ["return ":print i rest] +print i [IfToken:rest] = ["if":print i rest] +print i [ElseToken:rest] = ["else ":print i rest] +print i [WhileToken:rest] = ["while":print i rest] +print i [TrueToken:rest] = ["True":print i rest] +print i [FalseToken:rest] = ["False":print i rest] +print i [VoidToken:rest] = ["Void":print i rest] +print i [IntTypeToken:rest] = ["Int":print i rest] +print i [CharTypeToken:rest] = ["Char":print i rest] +print i [BoolTypeToken:rest] = ["Bool":print i rest] +print i [DoubleColonToken:rest] = [" :: ":print i rest] +print i [NotEqualToken:rest] = [" != ":print i rest] +print i [LesserEqToken:rest] = [" <= ":print i rest] +print i [GreaterEqToken:rest] = [" >= ":print i rest] +print i [EqualsToken:rest] = [" == ":print i rest] +print i [AmpersandsToken:rest] = [" && ":print i rest] +print i [PipesToken:rest] = [" || ":print i rest] +print i [ArrowToken:rest] = [" -> ":print i rest] +print i [BraceOpenToken:rest] = ["(":print i rest] +print i [BraceCloseToken:rest] = [")":print i rest] +print i [CBraceOpenToken:rest] = ["{\n":tab (i+1)] ++ print (i+1) rest +print i [CBraceCloseToken:rest] = case rest of + [CBraceCloseToken:_] = ["}\n":tab (i-2)] ++ print (i-1) rest + _ = ["}\n":tab (i-1)] ++ print (i-1) rest +print i [SquareOpenToken:rest] = ["[":print i rest] +print i [SquareCloseToken:rest] = ["]":print i rest] +print i [CommaToken:rest] = [", ":print i rest] +print i [ColonToken:rest] = [":":print i rest] +print i [SColonToken:rest] = case rest of + [CBraceCloseToken:_] = [";\n":tab (i-1)] ++ print i rest + _ = [";\n":tab i] ++ print i rest +print i [DotToken:rest] = [".":print i rest] +print i [PlusToken:rest] = [" + ":print i rest] +print i [DashToken:rest] = [" - ":print i rest] +print i [StarToken:rest] = [" * ":print i rest] +print i [SlashToken:rest] = [" / ":print i rest] +print i [PercentToken:rest] = [" % ":print i rest] +print i [AssignmentToken:rest] = [" = ":print i rest] +print i [LesserToken:rest] = [" < ":print i rest] +print i [BiggerToken:rest] = [" > ":print i rest] +print i [ExclamationToken:rest] = ["!":print i rest] +print i [EndOfFileToken:rest] = ["\n":print i rest]