example 2 for Component Pascal

samples/Component Pascal/Example2.cps

@@ -0,0 +1,71 @@
+MODULE ObxFact;
+(**
+    project         = "BlackBox"
+    organization    = "www.oberon.ch"
+    contributors    = "Oberon microsystems"
+    version         = "System/Rsrc/About"
+    copyright       = "System/Rsrc/About"
+    license         = "Docu/BB-License"
+    changes         = ""
+    issues          = ""
+
+**)
+
+IMPORT
+    Stores, Models, TextModels, TextControllers, Integers;
+
+PROCEDURE Read(r: TextModels.Reader; VAR x: Integers.Integer);
+    VAR i, len, beg: INTEGER; ch: CHAR; buf: POINTER TO ARRAY OF CHAR;
+BEGIN
+    r.ReadChar(ch);
+    WHILE ~r.eot & (ch <= " ") DO r.ReadChar(ch) END;
+    ASSERT(~r.eot & (((ch >= "0") & (ch <= "9")) OR (ch = "-")));
+    beg := r.Pos() - 1; len := 0;
+    REPEAT INC(len); r.ReadChar(ch) UNTIL r.eot OR (ch < "0") OR (ch > "9");
+    NEW(buf, len + 1);
+    i := 0; r.SetPos(beg);
+    REPEAT r.ReadChar(buf[i]); INC(i) UNTIL i = len;
+    buf[i] := 0X;
+    Integers.ConvertFromString(buf^, x)
+END Read;
+
+PROCEDURE Write(w: TextModels.Writer; x: Integers.Integer);
+    VAR i: INTEGER;
+BEGIN
+    IF Integers.Sign(x) < 0 THEN w.WriteChar("-") END;
+    i := Integers.Digits10Of(x);
+    IF i # 0 THEN
+        REPEAT DEC(i); w.WriteChar(Integers.ThisDigit10(x, i)) UNTIL i = 0
+    ELSE w.WriteChar("0")
+    END
+END Write;
+
+PROCEDURE Compute*;
+    VAR beg, end, i, n: INTEGER; ch: CHAR;
+        s: Stores.Operation;
+        r: TextModels.Reader; w: TextModels.Writer; attr: TextModels.Attributes;
+        c: TextControllers.Controller;
+        x: Integers.Integer;
+BEGIN
+    c := TextControllers.Focus();
+    IF (c # NIL) & c.HasSelection() THEN
+        c.GetSelection(beg, end);
+        r := c.text.NewReader(NIL); r.SetPos(beg); r.ReadChar(ch);
+        WHILE ~r.eot & (beg < end) & (ch <= " ") DO r.ReadChar(ch); INC(beg) END;
+        IF ~r.eot & (beg < end) THEN
+            r.ReadPrev; Read(r, x);
+            end := r.Pos(); r.ReadPrev; attr :=r.attr;
+            IF (Integers.Sign(x) > 0) & (Integers.Compare(x, Integers.Long(MAX(LONGINT))) <= 0) THEN
+                n := SHORT(Integers.Short(x)); i := 2; x := Integers.Long(1);
+                WHILE i <= n DO x := Integers.Product(x, Integers.Long(i)); INC(i) END;
+                Models.BeginScript(c.text, "computation", s);
+                c.text.Delete(beg, end);
+                w := c.text.NewWriter(NIL); w.SetPos(beg); w.SetAttr(attr);
+                Write(w, x);
+                Models.EndScript(c.text, s)
+            END
+        END
+    END
+END Compute;
+
+END ObxFact.