slight refactoring (move pure parsing functions to functional core in a separate file)

dotscape.mlb

@@ -1,28 +1,31 @@
 $(SML_LIB)/basis/basis.mlb
 
 (* FUNCTIONAL CORE *)
-functional-core/app-type.sml
+functional-core/app/app-type.sml
 
 ann
   "allowVectorExps true"
 in
-  functional-core/ndc.sml
-  functional-core/click-points.sml
-  functional-core/graph-lines.sml
-  functional-core/triangles.sml
+  functional-core/app/ndc.sml
+  functional-core/app/click-points.sml
+  functional-core/app/graph-lines.sml
+  functional-core/app/triangles.sml
 end
 
-functional-core/triangle-stage.sml
+functional-core/app/triangle-stage.sml
 
-functional-core/app-init.sml
-functional-core/app-with.sml
+functional-core/app/app-init.sml
+functional-core/app/app-with.sml
 
 message-types/input-msg.sml
 message-types/file-msg.sml
 message-types/draw-msg.sml
 message-types/update-msg.sml
 
-functional-core/app-update.sml
+functional-core/app/app-update.sml
+
+(* pure file parsing functions *)
+functional-core/file/parse-file.sml
 
 (* IMPERATIVE SHELL *)
 $(SML_LIB)/basis/mlton.mlb

functional-core/file/parse-file.sml

@@ -0,0 +1,55 @@
+signature PARSE_FILE =
+sig
+  val parseLine: string -> AppType.triangle option
+end
+
+structure ParseFile :> PARSE_FILE =
+struct
+  datatype triangle_token = X | Y | COORD of Real32.real | UNKNOWN of string
+
+  fun extractTriangle lst =
+    case lst of
+      [ X, COORD x1
+      , Y, COORD y1
+      , X, COORD x2
+
+      , Y, COORD y2
+      , X, COORD x3
+      , Y, COORD y3
+      ] => SOME {x1 = x1, y1 = y1, x2 = x2, y2 = y2, x3 = x3, y3 = y3}
+    | _ => NONE
+
+  fun tokeniseString str =
+    if str = "x" then
+      X
+    else if str = "y" then
+      Y
+    else
+      case Real32.fromString str of
+        SOME num => COORD num
+      | NONE => UNKNOWN str
+
+  fun helpParseLine (line, pos, acc, lastSpacePos) =
+    if pos = String.size line then
+      List.rev acc
+    else
+      let
+        val chr = String.sub (line, pos)
+      in
+        if chr = #" " orelse chr = #"\n" then
+          let
+            val strToken = String.substring
+              (line, lastSpacePos + 1, pos - (lastSpacePos + 1))
+            val token = tokeniseString strToken
+          in
+            helpParseLine (line, pos + 1, token :: acc, pos)
+          end
+        else
+          helpParseLine (line, pos + 1, acc, lastSpacePos)
+      end
+
+  fun parseLine line =
+    let val lst = helpParseLine (line, 0, [], ~1)
+    in extractTriangle lst
+    end
+end

imperative-shell/file-thread.sml

@@ -5,67 +5,18 @@ end
 
 structure FileThread :> FILE_THREAD =
 struct
-  open AppType
   open FileMessage
   open InputMessage
 
+  datatype parse_result = OK of AppType.triangle list | PARSE_ERROR
+
   val filename = "a.dsc"
 
-  datatype triangle_token = X | Y | COORD of Real32.real | UNKNOWN
-
-  fun extractTriangle lst =
-    case lst of
-      [ X, COORD x1
-      , Y, COORD y1
-      , X, COORD x2
-
-      , Y, COORD y2
-      , X, COORD x3
-      , Y, COORD y3
-      ] => SOME {x1 = x1, y1 = y1, x2 = x2, y2 = y2, x3 = x3, y3 = y3}
-    | _ => NONE
-
-  fun tokeniseString str =
-    if str = "x" then
-      X
-    else if str = "y" then
-      Y
-    else
-      case Real32.fromString str of
-        SOME num => COORD num
-      | NONE => UNKNOWN
-
-  fun helpParseLine (line, pos, acc, lastSpacePos) =
-    if pos = String.size line then
-      List.rev acc
-    else
-      let
-        val chr = String.sub (line, pos)
-      in
-        if chr = #" " orelse chr = #"\n" then
-          let
-            val strToken = String.substring
-              (line, lastSpacePos + 1, pos - (lastSpacePos + 1))
-            val token = tokeniseString strToken
-          in
-            helpParseLine (line, pos + 1, token :: acc, pos)
-          end
-        else
-          helpParseLine (line, pos + 1, acc, lastSpacePos)
-      end
-
-  fun parseLine line =
-    let val lst = helpParseLine (line, 0, [], ~1)
-    in extractTriangle lst
-    end
-
-  datatype parse_resule = OK of AppType.triangle list | PARSE_ERROR
-
   fun parse (io, acc) =
     case TextIO.inputLine io of
       SOME line =>
         let
-          val line = parseLine line
+          val line = ParseFile.parseLine line
         in
           (case line of
              SOME tri => parse (io, tri :: acc)
@@ -79,7 +30,7 @@ struct
       val triangles = parse (io, [])
       val _ = TextIO.closeIn io
 
-      val inputMsg = 
+      val inputMsg =
         case triangles of
           OK triangles => USE_TRIANGLES triangles
         | PARSE_ERROR => TRIANGLES_LOAD_ERROR
@@ -92,14 +43,14 @@ struct
       {x1, y1, x2, y2, x3, y3} :: tl =>
         let
           val triString = String.concat
-            [ "x " , Real32.toString x1
-            , " y " , Real32.toString y1
+            [ "x ", Real32.toString x1
+            , " y ", Real32.toString y1
 
-            , " x " , Real32.toString x2
-            , " y " , Real32.toString y2
+            , " x ", Real32.toString x2
+            , " y ", Real32.toString y2
 
-            , " x " , Real32.toString x3
-            , " y " , Real32.toString y3
+            , " x ", Real32.toString x3
+            , " y ", Real32.toString y3
             , "\n"
             ]