Rename project to Milch

15 files changed, 50 insertions, 32 deletions

diff --git a/README.md b/README.md
index fa1fec0..f3e2486 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,10 @@
-# lang
+# MILCH: [M]y functional language [I]nspired by [L]isp, [C]lojure, and [H]askell
+
+## Summary
+
+`MILCH` (or `Milch`, or `milch`) is a interpreted, dynamically typed functional programming language that has some Lisp-inspired syntax and Haskell-inspired semantics. Milch is german for 🥛.
+
+I'm developing this language by myself as a hobby, and the spec is going to change all the time. Some features documented here might not yet be implemented.
 
 Check out the language spec  
 [spec.md](spec.md)
@@ -6,6 +12,13 @@ Check out the language spec
 Check out the TODO  
 [todo.md](todo.md)
 
+## Usage
+
+Install a Haskell toolchain with Stack and GHC. Run
+
+    stack run -- -h
+
+to see the help text.
 
 ## Author
 
diff --git a/examples/effects-concept.lisp b/examples/effects-concept.milch
index 5ea90d7..5ea90d7 100644
--- a/examples/effects-concept.lisp
+++ b/examples/effects-concept.milch
diff --git a/examples/import.lisp b/examples/import.lisp
deleted file mode 100644
index 1a2f6f1..0000000
--- a/examples/import.lisp
+++ /dev/null
@@ -1,2 +0,0 @@
-(import! "stdlib/common.lisp")
-(import! M "stdlib/maybe.lisp")
diff --git a/examples/import.milch b/examples/import.milch
new file mode 100644
index 0000000..e839ef0
--- /dev/null
+++ b/examples/import.milch
@@ -0,0 +1,2 @@
+(import! "stdlib/common.milch")
+(import! M "stdlib/maybe.milch")
diff --git a/examples/impure-concept.lisp b/examples/impure-concept.milch
index 893b29e..893b29e 100644
--- a/examples/impure-concept.lisp
+++ b/examples/impure-concept.milch
diff --git a/examples/purity-test.lisp b/examples/purity-test.lisp
deleted file mode 100644
index 31e82d3..0000000
--- a/examples/purity-test.lisp
+++ /dev/null
@@ -1,20 +0,0 @@
-(let! f (\[x] x))
-(f 10)
-
-(let! g! (\![x] (print! x)))
-(g! "foo")
-
-(let! h (\[x] (g! x)))
-(h "bar")
-
-(let! main! (\![]
-    (print! (fmt "{0}\n" ["main"]))
-    ))
-
-(main!)
-
-(let! pure-main (\[]
-    (print! (fmt "{0}\n" ["pure-main"]))
-    ))
-
-(pure-main)
diff --git a/examples/purity-test.milch b/examples/purity-test.milch
new file mode 100644
index 0000000..6e8faea
--- /dev/null
+++ b/examples/purity-test.milch
@@ -0,0 +1,25 @@
+; utils
+
+(let! println! (\![x]
+    (print! (fmt "{0}\n" [x]))))
+
+; pure vs. impure demo
+
+; this is a pure function
+(let! f (\[x] x))
+
+(f 10) ; works
+
+; this is an impure function
+(let! g! (\![x] (println! x)))
+
+(g! "foo") ; works
+
+; this is a pure function that tries to call an impure function
+(let! h (\[x] (g! x)))
+
+(h "bar")
+; error: cannot call impure function in pure context
+;   when calling function g! at examples/purity-test.milch:19:15
+;   in a function definition at examples/purity-test.milch:19:12
+;   when calling function h at examples/purity-test.milch:21:1
diff --git a/examples/records-concept.lisp b/examples/records-concept.milch
index 420fa9f..420fa9f 100644
--- a/examples/records-concept.lisp
+++ b/examples/records-concept.milch
diff --git a/examples/test.lisp b/examples/test.milch
index fd8c379..fd8c379 100644
--- a/examples/test.lisp
+++ b/examples/test.milch
diff --git a/examples/types-concept.lisp b/examples/types-concept.milch
index 8359c6b..8359c6b 100644
--- a/examples/types-concept.lisp
+++ b/examples/types-concept.milch
diff --git a/src/Utils.hs b/src/Utils.hs
index 0cc17bd..b68de18 100644
--- a/src/Utils.hs
+++ b/src/Utils.hs
@@ -39,7 +39,7 @@ data LState = LState {
     stateConfig :: Config,
     stateEnv :: Env,
     stateDepth :: Int,
-    statePure :: LIsPure
+    statePure :: Purity
 }
 
 type LineNo = Int
@@ -92,12 +92,12 @@ getDepth = do
     s <- get
     return $ stateDepth s
 
-getPurity :: LContext LIsPure
+getPurity :: LContext Purity
 getPurity = do
     s <- get
     return $ statePure s
 
-isAllowedPurity :: LIsPure -> LContext Bool
+isAllowedPurity :: Purity -> LContext Bool
 isAllowedPurity purity = do
     s <- get
     let currentPurity = statePure s
@@ -105,11 +105,11 @@ isAllowedPurity purity = do
         False -> True -- if currently in impure context (false), all calls are ok
         True -> purity == True -- but if in pure context (true), only pure calls are ok
 
-updatePurity :: LIsPure -> LContext ()
+updatePurity :: Purity -> LContext ()
 updatePurity purity = do
     modify (\s -> s { statePure = purity })
 
-checkPurity :: LIsPure -> LContext ()
+checkPurity :: Purity -> LContext ()
 checkPurity purity = do
     purityOk <- isAllowedPurity purity
     when (not purityOk) $ throwL "" $ "cannot call impure function in pure context"
@@ -127,7 +127,7 @@ instance (Eq Token) where
 instance (Show Token) where
     show token = show $ tokenContent token
 
-type LIsPure = Bool
+type Purity = Bool
 type LFunction = AST -> LContext AST
 
 data ASTNode
@@ -139,7 +139,7 @@ data ASTNode
     | ASTVector [AST]
     | ASTFunctionCall [AST]
     | ASTHashMap (M.Map AST AST)
-    | ASTFunction LIsPure LFunction
+    | ASTFunction Purity LFunction
     | ASTUnit
     | ASTHole
 
diff --git a/stdlib/common.lisp b/stdlib/common.milch
index 4d5b132..4d5b132 100644
--- a/stdlib/common.lisp
+++ b/stdlib/common.milch
diff --git a/stdlib/maybe-with-unions.lisp b/stdlib/maybe-with-unions.milch
index 53a5024..53a5024 100644
--- a/stdlib/maybe-with-unions.lisp
+++ b/stdlib/maybe-with-unions.milch
diff --git a/stdlib/maybe.lisp b/stdlib/maybe.milch
index 086b0dc..086b0dc 100644
--- a/stdlib/maybe.lisp
+++ b/stdlib/maybe.milch
diff --git a/todo.md b/todo.md
index 231b0b4..6afd50d 100644
--- a/todo.md
+++ b/todo.md
@@ -2,7 +2,7 @@
 
 In order of priority
 
+- Implement records and unions
 - Write function let expressions properly using lookups
 - Write tests!
-- Come up with a name for the language
-- Add effects system (see `examples/effects-concept.lisp`)
+- Add effects system (see `examples/effects-concept.milch`)