diff --git a/src/Lib/Parser.idr b/src/Lib/Parser.idr
index 86f25f8..5fb7a40 100644
--- a/src/Lib/Parser.idr
+++ b/src/Lib/Parser.idr
@@ -42,6 +42,29 @@ stringLit = do
   t <- token StringKind
   pure $ RLit fc (LString (cast t))
 
+
+-- typeExpr is term with arrows.
+export typeExpr : Parser Raw
+export term : (Parser Raw)
+
+interp : Parser Raw
+interp = token StartInterp *> term <* token EndInterp
+
+
+interpString : Parser Raw
+interpString = do
+  fc <- getPos
+  ignore $ token StartQuote
+  part <- term
+  parts <- many (stringLit <|> interp)
+  ignore $ token EndQuote
+  pure $ foldl append part parts
+  where
+    append : Raw -> Raw -> Raw
+    append t u =
+      let fc = getFC t in
+      (RApp fc (RApp fc (RVar fc "_++_") t Explicit) u Explicit)
+
 intLit : Parser Raw
 intLit = do
   fc <- getPos
@@ -56,11 +79,9 @@ charLit = do
   pure $ RLit fc (LChar $ assert_total $ strIndex v 0)
 
 lit : Parser Raw
-lit = intLit <|> stringLit <|> charLit
+lit = intLit <|> interpString <|> stringLit <|> charLit
+
 
--- typeExpr is term with arrows.
-export typeExpr : Parser Raw
-export term : (Parser Raw)
 
 -- helpful when we've got some / many and need FC for each
 withPos : Parser a -> Parser (FC, a)
diff --git a/src/Lib/Token.idr b/src/Lib/Token.idr
index 2f7ff85..5437f82 100644
--- a/src/Lib/Token.idr
+++ b/src/Lib/Token.idr
@@ -42,6 +42,10 @@ data Kind
   | Semi
   | RBrace
   | EOI
+  | StartQuote
+  | EndQuote
+  | StartInterp
+  | EndInterp
 
 export
 Show Kind where
@@ -62,6 +66,10 @@ Show Kind where
   show StringKind = "String"
   show JSLit = "JSLit"
   show Projection = "Projection"
+  show StartQuote = "StartQuote"
+  show EndQuote = "EndQuote"
+  show StartInterp = "StartInterp"
+  show EndInterp = "EndInterp"
 
 export
 Eq Kind where
diff --git a/src/Lib/Tokenizer.idr b/src/Lib/Tokenizer.idr
index a33d5b0..86e20c4 100644
--- a/src/Lib/Tokenizer.idr
+++ b/src/Lib/Tokenizer.idr
@@ -2,6 +2,9 @@ module Lib.Tokenizer
 
 -- Working alternate tokenizer, saves about 2k, can be translated to newt
 
+-- Currently this processes a stream of characters, I may switch it to
+-- combinators for readability in the future.
+
 import Lib.Token
 import Lib.Common
 import Data.String
@@ -20,30 +23,78 @@ keywords = ["let", "in", "where", "case", "of", "data", "U", "do",
             "$", "λ", "?", "@", ".",
              "->", "→", ":", "=>", ":=", "=", "<-", "\\", "_", "|"]
 
+record TState where
+  constructor TS
+  trow : Int
+  tcol : Int
+  acc : SnocList BTok
+  chars : List Char
+
 -- This makes a big case tree...
-tokenise' : Int -> Int ->  SnocList BTok -> List Char -> Either Error (List BTok)
-tokenise' sl sc toks chars = case chars of
-  Nil => Right $ toks <>> []
-  ' ' :: cs => tokenise' sl (sc + 1) toks cs
-  '\n' :: cs => tokenise' (sl + 1) 0 toks cs
-  '{' :: '{' :: cs => tokenise' sl (sc + 2) (toks :< mktok False sl (sc + 2) Keyword "{{" ) cs
-  '}' :: '}' :: cs => tokenise' sl (sc + 2) (toks :< mktok False sl (sc + 2) Keyword "}}" ) cs
-  ',' :: cs => tokenise' sl (sc + 1) (toks :< mktok False sl (sc + 1) Ident ",") cs
-  '_' :: ',' :: '_' :: cs => tokenise' sl (sc + 3) (toks :< mktok False sl (sc + 3) MixFix "_,_") cs
-  '_' :: '.' :: '_' :: cs => tokenise' sl (sc + 3) (toks :< mktok False sl (sc + 3) MixFix "_._") cs
+rawTokenise : TState -> Either Error TState
+
+quoteTokenise : TState -> Int -> Int -> SnocList Char -> Either Error TState
+quoteTokenise ts@(TS el ec toks chars) sl sc acc = case chars of
+  '"' :: cs => Right (TS el ec (toks :< stok) chars)
+  '\\' :: '{' :: cs => do
+    let tok = MkBounded (Tok StartInterp "\\{") (MkBounds el ec el (ec + 2))
+    (TS sl sc toks chars) <- rawTokenise $ TS el (ec + 2) (toks :< stok :< tok) cs
+    case chars of
+      '}' :: cs =>
+        let tok = MkBounded (Tok EndInterp "}") (MkBounds el ec el (ec + 1))
+        in quoteTokenise (TS el (ec + 1) (toks :< tok) cs) el (ec + 1) [<]
+      cs => Left $ E (MkFC "" (el, ec)) "Expected '{'"
+  c :: cs => do
+    quoteTokenise (TS el (ec + 1) toks cs) sl sc (acc :< c)
+  Nil => Left $ E (MkFC "" (el, ec)) "Expected '\"' at EOF"
+
+  where
+    stok : BTok
+    stok = MkBounded (Tok StringKind (pack $ acc <>> [])) (MkBounds sl sc el ec)
+
+
+
+rawTokenise ts@(TS sl sc toks chars) = case chars of
+  Nil => Right $ ts
+  ' ' :: cs => rawTokenise (TS sl (sc + 1) toks cs)
+  '\n' :: cs => rawTokenise (TS (sl + 1) 0 toks cs)
+  '{' :: '{' :: cs => rawTokenise (TS sl (sc + 2) (toks :< mktok False sl (sc + 2) Keyword "{{" ) cs)
+  '}' :: '}' :: cs => rawTokenise (TS sl (sc + 2) (toks :< mktok False sl (sc + 2) Keyword "}}" ) cs)
+
+  '"' :: cs => do
+    let tok = mktok False sl (sc + 1) StartQuote "\""
+    (TS sl sc toks chars) <- quoteTokenise (TS sl (sc + 1) (toks :< tok) cs) sl (sc + 1) [<]
+    case chars of
+      '"' :: cs => let tok = mktok False sl (sc + 1) EndQuote "\"" in
+        rawTokenise (TS sl (sc + 1) (toks :< tok) cs)
+      cs => Left $ E (MkFC "" (sl, sc)) "Expected '\"'"
+
+
+  '}' :: cs => Right ts
+  '{' :: cs => do
+    let tok = mktok False sl (sc + 1) Symbol "{"
+    (TS sl sc toks chars) <- rawTokenise (TS sl (sc + 1) (toks :< tok) cs)
+    case chars of
+      '}' :: cs => let tok = mktok False sl (sc + 1) Symbol "}" in
+        rawTokenise (TS sl (sc + 1) (toks :< tok) cs)
+      cs => Left $ E (MkFC "" (sl, sc)) "Expected '}'"
+
+  ',' :: cs => rawTokenise (TS sl (sc + 1) (toks :< mktok False sl (sc + 1) Ident ",") cs)
+  '_' :: ',' :: '_' :: cs => rawTokenise (TS sl (sc + 3) (toks :< mktok False sl (sc + 3) MixFix "_,_") cs)
+  '_' :: '.' :: '_' :: cs => rawTokenise (TS sl (sc + 3) (toks :< mktok False sl (sc + 3) MixFix "_._") cs)
   '\'' :: '\\' :: c :: '\'' :: cs =>
     let ch = ifThenElse (c == 'n') '\n' c
-    in tokenise' sl (sc + 4) (toks :< mktok False sl (sc + 4) Character (singleton ch)) cs
-  '\'' :: c :: '\'' :: cs => tokenise' sl (sc + 3) (toks :< mktok False sl (sc + 3) Character (singleton c)) cs
+    in rawTokenise (TS sl (sc + 4) (toks :< mktok False sl (sc + 4) Character (singleton ch)) cs)
+  '\'' :: c :: '\'' :: cs => rawTokenise (TS sl (sc + 3) (toks :< mktok False sl (sc + 3) Character (singleton c)) cs)
   '#' :: cs => ?do_pragma -- we probably want to require at least one alpha?
-  '-' :: '-' :: cs => lineComment sl (sc + 2) toks cs
-  '/' :: '-' :: cs => blockComment sl (sc + 2) toks cs
-  '`' :: cs => doBacktick sl (sc + 1) toks cs [<]
-  '"' :: cs => doQuote sl (sc + 1) toks cs [<]
-  '.' :: cs => doRest sl (sc + 1) toks cs Projection isIdent (Lin :< '.')
+  '-' :: '-' :: cs => lineComment (TS sl (sc + 2) toks cs)
+  '/' :: '-' :: cs => blockComment (TS sl (sc + 2) toks cs)
+  '`' :: cs => doBacktick (TS sl (sc + 1) toks cs) [<]
+  '"' :: cs => doQuote (TS sl (sc + 1) toks cs) [<]
+  '.' :: cs => doRest (TS sl (sc + 1) toks cs) Projection isIdent (Lin :< '.')
   '-' :: c :: cs => if isDigit c
-    then doRest sl (sc + 2) toks cs Number isDigit (Lin :< '-' :< c)
-    else doRest sl (sc + 1) toks (c :: cs) Ident isIdent (Lin :< '-')
+    then doRest (TS sl (sc + 2) toks cs) Number isDigit (Lin :< '-' :< c)
+    else doRest (TS sl (sc + 1) toks (c :: cs)) Ident isIdent (Lin :< '-')
 
   c :: cs => doChar c cs
 
@@ -54,13 +105,13 @@ tokenise' sl sc toks chars = case chars of
     isUIdent : Char -> Bool
     isUIdent c = isIdent c || c == '.'
 
-    doBacktick : Int -> Int -> SnocList BTok -> List Char -> SnocList Char -> Either Error (List BTok)
-    doBacktick l c toks Nil acc = Left $ E (MkFC "" (l,c)) "EOF in backtick string"
-    doBacktick el ec toks ('`' :: cs) acc =
+    doBacktick : TState -> SnocList Char -> Either Error TState
+    doBacktick (TS l c toks Nil) acc = Left $ E (MkFC "" (l,c)) "EOF in backtick string"
+    doBacktick (TS el ec toks ('`' :: cs)) acc =
       let tok = MkBounded (Tok JSLit (pack $ acc <>> [])) (MkBounds sl sc el ec) in
-      tokenise' el (ec + 1) (toks :< tok) cs
-    doBacktick l c toks ('\n' :: cs) acc = doBacktick (l + 1) 0 toks cs (acc :< '\n')
-    doBacktick l c toks (ch :: cs) acc = doBacktick l (c + 1) toks cs (acc :< ch)
+      rawTokenise (TS el (ec + 1) (toks :< tok) cs)
+    doBacktick (TS l c toks ('\n' :: cs)) acc = doBacktick (TS (l + 1) 0 toks cs) (acc :< '\n')
+    doBacktick (TS l c toks (ch :: cs)) acc = doBacktick (TS l (c + 1) toks cs) (acc :< ch)
 
 
     -- temporary use same token as before
@@ -68,42 +119,45 @@ tokenise' sl sc toks chars = case chars of
     mktok checkkw el ec kind text = let kind = if checkkw && elem text keywords then Keyword else kind in
       MkBounded (Tok kind text) (MkBounds sl sc el ec)
 
-    lineComment : Int -> Int -> SnocList BTok -> List Char -> Either Error (List BTok)
-    lineComment line col toks Nil = tokenise' line col toks Nil
-    lineComment line col toks ('\n' :: cs) = tokenise' (line + 1) 0 toks cs
-    lineComment line col toks (c :: cs) = lineComment line (col + 1) toks cs
+    lineComment : TState -> Either Error TState
+    lineComment (TS line col toks Nil) = rawTokenise (TS line col toks Nil)
+    lineComment (TS line col toks ('\n' :: cs)) = rawTokenise (TS (line + 1) 0 toks cs)
+    lineComment (TS line col toks (c :: cs)) = lineComment (TS line (col + 1) toks cs)
 
-    blockComment : Int -> Int -> SnocList BTok -> List Char -> Either Error (List BTok)
-    blockComment line col toks Nil = Left $ E (MkFC "" (line, col)) "EOF in block comment"
-    blockComment line col toks ('-' :: '/' :: cs) = tokenise' line (col + 2) toks cs
-    blockComment line col toks ('\n' :: cs) = blockComment (line + 1) 0 toks cs
-    blockComment line col toks (c :: cs) = blockComment line (col + 1) toks cs
+    blockComment : TState -> Either Error TState
+    blockComment (TS line col toks Nil) = Left $ E (MkFC "" (line, col)) "EOF in block comment"
+    blockComment (TS line col toks ('-' :: '/' :: cs)) = rawTokenise (TS line (col + 2) toks cs)
+    blockComment (TS line col toks ('\n' :: cs)) = blockComment (TS (line + 1) 0 toks cs)
+    blockComment (TS line col toks (c :: cs)) = blockComment (TS line (col + 1) toks cs)
 
-    doRest : Int -> Int -> SnocList BTok -> List Char -> Kind -> (Char -> Bool) -> SnocList Char -> Either Error (List BTok)
-    doRest l c toks Nil kind pred acc = tokenise' l c (toks :< mktok True l c kind (pack $ acc <>> [])) Nil
-    doRest l c toks (ch :: cs) kind pred acc = if pred ch
-      then doRest l (c + 1) toks cs kind pred (acc :< ch)
+    doRest : TState -> Kind -> (Char -> Bool) -> SnocList Char -> Either Error TState
+    doRest (TS l c toks Nil) kind pred acc = rawTokenise (TS l c (toks :< mktok True l c kind (pack $ acc <>> [])) Nil)
+    doRest (TS l c toks (ch :: cs)) kind pred acc = if pred ch
+      then doRest (TS l (c + 1) toks cs) kind pred (acc :< ch)
       else
         let kind = if elem '_' acc then MixFix else kind in
-        tokenise' l c (toks :< mktok True l (c - 1) kind (pack $ acc <>> [])) (ch :: cs)
+        rawTokenise (TS l c (toks :< mktok True l (c - 1) kind (pack $ acc <>> [])) (ch :: cs))
 
-    doQuote : Int -> Int -> SnocList BTok -> List Char -> SnocList Char -> Either Error (List BTok)
+    doQuote : TState -> SnocList Char -> Either Error TState
     -- should be an error..
-    doQuote line col toks Nil acc = ?missing_end_quote
-    doQuote line col toks ('\\' :: 'n' :: cs) acc = doQuote line (col + 2) toks cs (acc :< '\n')
-    doQuote line col toks ('\\' :: c :: cs) acc = doQuote line (col + 2) toks cs (acc :< c)
-    doQuote line col toks ('\n' :: cs) acc = ?error_newline_in_quote
-    doQuote line col toks ('"' :: cs) acc = tokenise' line (col + 1) (toks :< mktok False line (col + 1) StringKind (pack $ acc <>> [])) cs
-    doQuote line col toks (c :: cs) acc = doQuote line (col + 1) toks cs (acc :< c)
+    doQuote (TS line col toks Nil) acc = ?missing_end_quote
+    doQuote (TS line col toks ('\\' :: 'n' :: cs)) acc = doQuote (TS line (col + 2) toks cs) (acc :< '\n')
+    doQuote (TS line col toks ('\\' :: c :: cs)) acc = doQuote (TS line (col + 2) toks cs) (acc :< c)
+    doQuote (TS line col toks ('\n' :: cs)) acc = ?error_newline_in_quote
+    doQuote (TS line col toks ('"' :: cs)) acc = rawTokenise (TS line (col + 1) (toks :< mktok False line (col + 1) StringKind (pack $ acc <>> [])) cs)
+    doQuote (TS line col toks (c :: cs)) acc = doQuote (TS line (col + 1) toks cs) (acc :< c)
 
-    doChar : Char -> List Char ->  Either Error (List BTok)
+    doChar : Char -> List Char ->  Either Error TState
     doChar c cs = if elem c standalone
-      then tokenise' sl (sc + 1) (toks :< mktok True sl (sc + 1) Symbol (singleton c)) cs
+      then rawTokenise (TS sl (sc + 1) (toks :< mktok True sl (sc + 1) Symbol (singleton c)) cs)
       else let kind = if isDigit c then Number else if isUpper c then UIdent else Ident in
-        doRest sl sc toks (c :: cs) kind isIdent [<]
+        doRest (TS sl sc toks (c :: cs)) kind isIdent [<]
 
 export
 tokenise : String -> String -> Either Error (List BTok)
-tokenise fn text = case tokenise' 0 0 Lin (unpack text) of
-  Left (E (MkFC file start) str) => Left (E (MkFC fn start) str)
-  res => res
+tokenise fn text = case rawTokenise (TS 0 0 Lin (unpack text)) of
+  Right (TS trow tcol acc []) => Right $ acc <>> []
+  Right (TS trow tcol acc chars) => Left $ E (MkFC fn (trow, tcol)) "Extra toks"
+  Left (E (MkFC file start) str) => Left $ E (MkFC fn start) str
+  Left err => Left err
+