From 17c7f3846314f828084e228a6cb5ddf5bb5549e2 Mon Sep 17 00:00:00 2001
From: Camil Staps <info@camilstaps.nl>
Date: Fri, 24 Apr 2015 18:46:45 +0200
Subject: [PATCH] IT WORKS =====D

---
 fp2/week2/camil/StdIOMonad.dcl |  40 ++++++++++
 fp2/week2/camil/StdIOMonad.icl | 130 +++++++++++++++++++++++++++++++++
 fp2/week2/camil/StdMaybe.dcl   |  41 +++++++++++
 fp2/week2/camil/StdMaybe.icl   |  65 +++++++++++++++++
 fp2/week2/camil/StdMonad.dcl   |   8 ++
 fp2/week2/camil/StdMonad.icl   |   1 +
 6 files changed, 285 insertions(+)
 create mode 100644 fp2/week2/camil/StdIOMonad.dcl
 create mode 100644 fp2/week2/camil/StdIOMonad.icl
 create mode 100644 fp2/week2/camil/StdMaybe.dcl
 create mode 100644 fp2/week2/camil/StdMaybe.icl
 create mode 100644 fp2/week2/camil/StdMonad.dcl
 create mode 100644 fp2/week2/camil/StdMonad.icl

diff --git a/fp2/week2/camil/StdIOMonad.dcl b/fp2/week2/camil/StdIOMonad.dcl
new file mode 100644
index 0000000..a23a328
--- /dev/null
+++ b/fp2/week2/camil/StdIOMonad.dcl
@@ -0,0 +1,40 @@
+definition module StdIOMonad
+
+//	Deze module verpakt een aantal StdFile functies in een monadische jas
+
+import StdMonad
+
+:: IO a
+:: *W
+:: Void       = Void
+:: Filemode   = Lees | Schrijf
+:: Filenaam :== String
+:: Filehandle
+
+//	voer monadische I/O actie uit op de wereld:
+doIO:: (IO a) *World -> *(a, *W)
+
+//  IO is een monad:
+instance return IO
+instance >>=    IO
+
+//	lees regel van de console:
+read		:: IO String
+
+//	schrijf regel naar de console:
+write		:: String -> IO Void
+
+//	open de file met gegeven filenaam en mode:
+//open		:: Filenaam Filemode -> IO (Maybe Filehandle)
+
+//	sluit de file met gegeven filenaam:
+//close		:: Filehandle -> IO Bool
+//
+////	bepaal of het lezen van de file klaar is:
+//eof			:: Filehandle -> IO Bool
+//
+////	lees een regel van een file:
+//readline	:: Filehandle -> IO (Maybe String)
+//
+////	schrijf een regel naar een file:
+//writeline	:: String Filehandle -> IO Bool
diff --git a/fp2/week2/camil/StdIOMonad.icl b/fp2/week2/camil/StdIOMonad.icl
new file mode 100644
index 0000000..c25cb4c
--- /dev/null
+++ b/fp2/week2/camil/StdIOMonad.icl
@@ -0,0 +1,130 @@
+implementation module StdIOMonad
+
+import StdBool
+import StdEnum
+import StdFile
+import StdList
+import StdMaybe
+import StdMisc
+import StdMonad
+import StdOverloaded
+import StdString
+import StdTuple
+
+:: IO a = IO (*W -> *(a, *W))
+:: *W :== *(*World, *[*(Filehandle, *File)])
+:: Filemode = Lees | Schrijf
+:: Filenaam :== String
+:: Filehandle :== String
+
+instance toInt Filemode where
+	toInt Lees = FReadText
+	toInt Schrijf = FWriteText
+
+//voer monadische I/O actie uit op de wereld:
+doIO:: (IO a) *World -> *(a, *W)
+doIO (IO f) w = f (w, [])
+
+unIO:: (IO a) -> *W -> *(a, *W)
+unIO (IO f) = f 
+
+//  IO is een monad:
+instance return IO where
+	return x = IO (\w -> (x, w))
+instance >>=    IO where
+	(>>=) (IO f) g = IO (\w = let (a, w1) = f w in unIO (g a) w1)
+
+read:: IO String
+read = IO read`
+	where
+		read`:: *W -> *(String, *W)
+		read` (world, s)
+		# (io, world) = stdio world
+		# (line, io) = freadline io
+		# (_, world) = fclose io world
+		= (line, (world, s))
+
+//	schrijf regel naar de console:
+write		:: String -> IO Void
+write s = IO (write` s)
+	where
+		write`:: String *W -> *(Void, *W)
+		write` line (world, s)
+		# (io, world) = stdio world
+		# io = io <<< line
+		# (_, world) = fclose io world
+		= (Void, (world, s))
+
+//	open de file met gegeven filenaam en mode:
+find:: Filehandle *[*(Filehandle, *File)] -> (Maybe *(Filehandle, *File), *[*(Filehandle, *File)]) 
+find fh fs
+# (fhs, fis) = unzip fs
+# fhsC = zip2 [0..length fhs] fhs
+# index = [(i, h) \\ (i, h) <- fhsC | h == fh]
+| length index == 0 = (Nothing, zip2 fhs fis)
+# index = fst (hd index)
+# (fis1, fis2) = splitAt index fis
+# (fhs1, fhs2) = splitAt index fhs
+# (thefile, fis2) = splitAt 1 fis2
+# (thehandle, fhs2) = splitAt 1 fhs2
+= (Just (hd thehandle, hd thefile), zip2 (fhs1 ++ fhs2) (fis1 ++ fis2))
+
+
+open:: Filenaam Filemode -> IO (Maybe Filehandle)
+open s m = IO (open` s m)
+	where
+		open`:: String Filemode *W -> *(Maybe Filehandle, *W)
+		open` fp m (world, fs)
+		| any (\l = fp == fst l) fs = (Nothing, (world, fs))
+		# (ok, file, world) = fopen fp (toInt m) world
+		= (Just fp, (world, [(fp, file):fs]))
+
+//	sluit de file met gegeven filenaam:
+close:: Filehandle -> IO Bool
+close fh = IO (close` fh)
+	where
+		close`:: Filehandle *W -> *(Bool, *W)
+		close` fp (world, fs)
+		# (currentfiletuple, fs) = find fp fs
+		| isNothing currentfiletuple = (False, (world, fs))
+		# (currentfh, currentfile) = fromJust currentfiletuple
+		# (ok, world) = fclose currentfile world
+		| not ok = abort "File can't be closed"
+		| otherwise = (True, (world, fs))
+		
+
+//	bepaal of het lezen van de file klaar is:
+eof			:: Filehandle -> IO Bool
+eof fh = IO (eof` fh)
+	where 
+		eof`:: Filehandle *W -> *(Bool, *W)
+		eof` fp (world, fs)
+		# (currentfiletuple, fs) = find fp fs
+		| isNothing currentfiletuple = abort "Can't do eof on non-existing file"
+		# (currentfh, currentfile) = fromJust currentfiletuple
+		# (ok, file) = fend currentfile
+		= (ok, (world, [(currentfh, file):fs]))
+
+//	lees een regel van een file:
+readline	:: Filehandle -> IO (Maybe String)
+readline fh = IO (readline` fh)
+	where
+		readline` :: Filehandle *W -> *(Maybe String, *W)
+		readline` fh (world, fs)
+		# (currentfiletuple, fs) = find fh fs
+		| isNothing currentfiletuple = (Nothing, (world, fs))
+		# (currentfh, currentfile) = fromJust currentfiletuple
+		# (s, currentfile) = freadline currentfile
+		= (Just s, (world, [(currentfh, currentfile):fs]))
+
+//	schrijf een regel naar een file:
+writeline	:: String Filehandle -> IO Bool
+writeline s fh = IO (writeline` s fh)
+	where
+		writeline` :: String Filehandle *W -> *(Bool, *W)
+		writeline` s fh (world, fs)
+		# (currentfiletuple, fs) = find fh fs
+		| isNothing currentfiletuple = (True, (world, fs))
+		# (currentfh, currentfile) = fromJust currentfiletuple
+		# currentfile = fwrites (s +++ "\n") currentfile
+		= (True, (world, [(currentfh, currentfile):fs]))
diff --git a/fp2/week2/camil/StdMaybe.dcl b/fp2/week2/camil/StdMaybe.dcl
new file mode 100644
index 0000000..2403683
--- /dev/null
+++ b/fp2/week2/camil/StdMaybe.dcl
@@ -0,0 +1,41 @@
+definition module StdMaybe
+
+//	********************************************************************************
+//	Clean StdLib library module, version 1.0
+//	********************************************************************************
+
+from StdFunc import :: St;
+from StdOverloaded import class ==(..);
+
+::	Maybe x
+	=	Just x
+	|	Nothing
+
+isJust		:: !(Maybe .x) -> Bool		// case @1 of (Just _) -> True; _ -> False
+isNothing	:: !(Maybe .x) -> Bool		// not o isJust
+fromJust	:: !(Maybe .x) -> .x		// \(Just x) -> x
+
+// for possibly unique elements:
+u_isJust :: !u:(Maybe .x) -> (!Bool, !u:Maybe .x)
+u_isNothing :: !u:(Maybe .x) -> (!Bool, !u:Maybe .x)
+
+accMaybe :: .(St .x .a) !u:(Maybe .x) -> (!Maybe .a,!u:Maybe .x)
+// accMaybe f (Just x) = (Just (fst (f x)),Just (snd (f x)))
+// accMaybe f Nothing  = (Nothing,Nothing)
+
+mapMaybe	:: .(.x -> .y) !(Maybe .x) -> Maybe .y
+// mapMaybe f (Just x) = Just (f x)
+// mapMaybe f Nothing  = Nothing
+
+instance ==       (Maybe x) | == x
+//	Nothing==Nothing
+//	Just a ==Just b <= a==b
+
+maybeToList :: !(Maybe .a) -> [.a];
+//	returns list with no or one element
+
+listToMaybe :: ![.a] -> .Maybe .a;
+//	returns Just head of list if possible
+
+catMaybes :: ![Maybe .a] -> .[.a];
+//	catMaybes ms =  [ m \\ Just m <- ms ]
diff --git a/fp2/week2/camil/StdMaybe.icl b/fp2/week2/camil/StdMaybe.icl
new file mode 100644
index 0000000..4eed325
--- /dev/null
+++ b/fp2/week2/camil/StdMaybe.icl
@@ -0,0 +1,65 @@
+implementation module StdMaybe
+
+//	********************************************************************************
+//	Clean StdLib library module, version 1.0
+//	********************************************************************************
+
+from StdFunc import :: St;
+from StdOverloaded import class ==(..);
+
+::	Maybe x
+	=	Just x
+	|	Nothing
+
+isJust :: !(Maybe .x) -> Bool
+isJust Nothing	= False
+isJust _		= True
+
+isNothing :: !(Maybe .x) -> Bool
+isNothing Nothing	= True
+isNothing _		= False
+
+u_isJust :: !u:(Maybe .x) -> (!Bool, !u:Maybe .x)
+u_isJust nothing=:Nothing
+	= (False, nothing)
+u_isJust just
+	= (True, just)
+
+u_isNothing :: !u:(Maybe .x) -> (!Bool, !u:Maybe .x)
+u_isNothing nothing=:Nothing
+	= (True, nothing)
+u_isNothing just
+	= (False,just)
+
+fromJust :: !(Maybe .x) -> .x
+fromJust (Just x) = x
+
+accMaybe :: .(St .x .a) !u:(Maybe .x) -> (!Maybe .a,!u:Maybe .x)
+accMaybe f (Just x)
+	# (a,x) = f x
+	= (Just a,Just x)
+accMaybe _ nothing
+	= (Nothing,nothing)
+
+mapMaybe :: .(.x -> .y) !(Maybe .x) -> Maybe .y
+mapMaybe f (Just x) = Just (f x)
+mapMaybe _ nothing  = Nothing
+
+instance == (Maybe x) | == x where
+	(==) Nothing  maybe	= case maybe of
+							Nothing -> True
+							just    -> False
+	(==) (Just a) maybe	= case maybe of
+							Just b  -> a==b
+							nothing -> False
+
+maybeToList :: !(Maybe .a) -> [.a];
+maybeToList Nothing    =  []
+maybeToList (Just a)   =  [a]
+
+listToMaybe :: ![.a] -> .Maybe .a;
+listToMaybe []         =  Nothing
+listToMaybe [a:_]      =  Just a
+ 
+catMaybes :: ![Maybe .a] -> .[.a];
+catMaybes ms           =  [ m \\ Just m <- ms ]
diff --git a/fp2/week2/camil/StdMonad.dcl b/fp2/week2/camil/StdMonad.dcl
new file mode 100644
index 0000000..cd1c654
--- /dev/null
+++ b/fp2/week2/camil/StdMonad.dcl
@@ -0,0 +1,8 @@
+definition module StdMonad
+
+class return        c :: a -> c a
+class (>>=) infix 0	c :: (c a) (a -> c b) -> c b
+class fail          c :: c a
+
+class Monad	        c | return, >>= c
+class MonadFail	    c | Monad, fail c
diff --git a/fp2/week2/camil/StdMonad.icl b/fp2/week2/camil/StdMonad.icl
new file mode 100644
index 0000000..db193ab
--- /dev/null
+++ b/fp2/week2/camil/StdMonad.icl
@@ -0,0 +1 @@
+implementation module StdMonad
-- 
2.20.1