reserved storage locations can have initial values.

README.markdown

@@ -122,9 +122,10 @@ an added `foldr` or two would not be unwelcome...
 TODO
 ----
 
-*   Initial values for reserved, incl. tables
+*   Initial values for reserved tables
 *   give length for tables, must be there for reserved, if no init val
 *   Character tables ("strings" to everybody else)
+*   Put uninitialized `reserve`d data in uninitialized data segment
 *   Addressing modes — indexed mode on more instructions
 *   `jsr (vector)`
 *   `jmp routine`

doc/Checking.markdown

@@ -69,6 +69,17 @@ to all routines.
     | }
     = True
 
+An address declared with `reserve` may be given an initial value.
+
+    | reserve byte lives : 3
+    | routine main {
+    |    sta lives
+    | }
+    | routine died {
+    |    dec lives
+    | }
+    = True
+
 An address may be declared with `locate`, which is like `.alias` in an
 assembler, with the understanding that the value will be treated "like an
 address."  This is generally an address into the operating system or hardware

doc/Emitting.markdown

@@ -36,29 +36,29 @@ Emitting an `if`.
 Emitting a `repeat`.
 
     | assign byte screen 1024
-    | reserve byte zero
+    | reserve byte four : $04
     | routine main {
-    |    ldy zero
+    |    ldy four
     |    repeat bne {
     |       inc screen
     |       dey
-    |       cpy zero
+    |       cpy four
     |    }
     |    sty screen
     | }
     = main:
-    =   ldy zero
+    =   ldy four
     =   
     = _repeat_1:
     =   inc screen
     =   dey
-    =   cpy zero
+    =   cpy four
     =   BNE _repeat_1
     =   sty screen
     =   rts
     = 
     = .alias screen 1024
-    = zero: .byte 0
+    = four: .byte 4
 
 Nested ifs.
 

src/SixtyPical/Checker.hs

@@ -31,7 +31,7 @@ noIndexedAccessOfNonTables p@(Program decls routines) =
         checkInstr j@(COPY _ (Indexed (NamedLocation sz g) reg)) =
             case lookupDecl p g of
                 Just (Assign _ ByteTable _) -> j
-                Just (Reserve _ ByteTable) -> j
+                Just (Reserve _ ByteTable _) -> j
                 Just _ -> (COPY A A)
                 Nothing -> (COPY A A)
         checkInstr other = other

src/SixtyPical/Emitter.hs

@@ -20,9 +20,15 @@ emitDecls p (decl:decls) =
     emitDecl p decl ++ "\n" ++ emitDecls p decls
 
 emitDecl p (Assign name _ addr) = ".alias " ++ name ++ " " ++ (show addr)
-emitDecl p (Reserve name Byte) = name ++ ": .byte 0"
-emitDecl p (Reserve name Word) = name ++ ": .word 0"
-emitDecl p (Reserve name Vector) = name ++ ": .word 0"
+emitDecl p (Reserve name typ value)
+    | typ == Byte = name ++ ": .byte " ++ val
+    | typ == Word = name ++ ": .word " ++ val
+    | typ == Vector = name ++ ": .word " ++ val
+    where
+       val = case value of
+           (Just v) -> (show v)
+           Nothing -> "0"
+
 emitDecl p (External name addr) = ".alias " ++ name ++ " " ++ (show addr)
 emitDecl p d = error (
     "Internal error: sixtypical doesn't know how to " ++

src/SixtyPical/Model.hs

@@ -47,7 +47,7 @@ data StorageLocation = A
 -- -- -- -- program model -- -- -- --
 
 data Decl = Assign LocationName StorageType Address -- .alias
-          | Reserve LocationName StorageType -- .word, .byte
+          | Reserve LocationName StorageType (Maybe DataValue) -- .word, .byte
           | External RoutineName Address
     deriving (Show, Ord, Eq)
 
@@ -93,13 +93,13 @@ programSummary p@(Program decls routs) =
 getRoutineName (Routine name _ _) = name
 
 getDeclLocationName (Assign name _ _) = name
-getDeclLocationName (Reserve name _) = name
+getDeclLocationName (Reserve name _ _) = name
 
 getDeclLocationType (Assign _ t _) = t
-getDeclLocationType (Reserve _ t) = t
+getDeclLocationType (Reserve _ t _) = t
 
 isLocationDecl (Assign _ _ _) = True
-isLocationDecl (Reserve _ _) = True
+isLocationDecl (Reserve _ _ _) = True
 isLocationDecl _ = False
 
 declaredLocationNames (Program decls _) =

src/SixtyPical/Parser.hs

@@ -11,10 +11,10 @@ import SixtyPical.Model
 {-
 
 Toplevel := {Decl} {Routine}.
-Decl     := "reserve" StorageType LocationName
-          | "assign" StorageType LocationName Address
+Decl     := "reserve" StorageType LocationName [":" Literal]
+          | "assign" StorageType LocationName Literal
           | "external" RoutineName Address.
-StorageType := "byte" | "word" | "vector".
+StorageType := "byte" | "word" | "byte table" | "vector".
 Routine  := "routine" RoutineName ["outputs" "(" {LocationName} ")"] Block.
 Block    := "{" {Command} "}".
 Command  := "if" Branch Block "else" Block
@@ -68,7 +68,11 @@ reserve = do
     nspaces
     sz <- storage_type
     name <- location_name
-    return $ Reserve name sz
+    value <- option Nothing (do{ string ":";
+                                 nspaces;
+                                 x <- literal_data_value;
+                                 return $ Just x })
+    return $ Reserve name sz value
 
 assign :: Parser Decl
 assign = do
@@ -76,7 +80,7 @@ assign = do
     nspaces
     sz <- storage_type
     name <- location_name
-    addr <- address
+    addr <- literal_address
     return $ Assign name sz addr
 
 external :: Parser Decl
@@ -84,7 +88,7 @@ external = do
     string "external"
     nspaces
     name <- routineName
-    addr <- address
+    addr <- literal_address
     return $ External name addr
 
 get_storage "byte" = Byte
@@ -196,7 +200,7 @@ register_location = do
 immediate :: Parser AddressingModality
 immediate = do
     string "#"
-    v <- data_value
+    v <- literal_data_value
     return $ Immediately v
 
 addressing_mode :: String -> (AddressingModality -> [StorageLocation] -> Instruction) -> Parser Instruction
@@ -585,37 +589,29 @@ named_location = do
     name <- location_name
     return (NamedLocation Nothing name)
 
-address = hex_address <|> decimal_address
+literal_address = do
+    a <- literal_value
+    return (a :: Address)
 
-hex_address :: Parser Address
-hex_address = do
+literal_data_value = do
+    a <- literal_value
+    return (a :: DataValue)
+
+literal_value = hex_literal <|> decimal_literal
+
+hex_literal :: Parser Int
+hex_literal = do
     char '$'
     digits <- many hexDigit
     nspaces
     let ((d, _):_) = readHex digits
-    return (d :: Address)
+    return d
 
-decimal_address :: Parser Address
-decimal_address = do
+decimal_literal :: Parser Int
+decimal_literal = do
     digits <- many digit
     nspaces
-    return (read digits :: Address)
-
-data_value = hex_data_value <|> decimal_data_value
-
-hex_data_value :: Parser DataValue
-hex_data_value = do
-    char '$'
-    digits <- many hexDigit
-    nspaces
-    let ((d, _):_) = readHex digits
-    return (d :: DataValue)
-
-decimal_data_value :: Parser DataValue
-decimal_data_value = do
-    digits <- many digit
-    nspaces
-    return (read digits :: DataValue)
+    return $ read digits
 
 -- -- -- driver -- -- --