From 12bdfc054fa28362ae054d574c1e843d93c8834b Mon Sep 17 00:00:00 2001
From: Jeremy Rand <jeremy@rand-family.com>
Date: Thu, 8 Aug 2013 00:58:18 -0400
Subject: [PATCH] More work on the NDA

---
 abCalcNDA.c    | 28 ++++++++++++++++++++++++++--
 abCalcNDA.defs |  8 +++++---
 abCalcNDA.rez  |  7 +++++++
 ops/abCOp.c    |  1 +
 4 files changed, 39 insertions(+), 5 deletions(-)

diff --git a/abCalcNDA.c b/abCalcNDA.c
index c9f3922..6dda4c8 100644
--- a/abCalcNDA.c
+++ b/abCalcNDA.c
@@ -240,6 +240,20 @@ void UpdateStack(void)
 }
 
 
+BOOLEAN ErrorRaised(void)
+{
+    char *errorString = abCalcGetError();
+    if (errorString == NULL) {
+        return FALSE;
+    }
+
+    AlertWindow(awCString+awResource, (Pointer)&errorString, abCalcErrorAlert);
+
+    abCalcClearError(); 
+    return TRUE;
+}
+
+
 void PushCalcEntry(CtlRecHndl entryBox)
 {
     static Str255 strBuf;
@@ -274,9 +288,12 @@ void ExecCalcCmd(char *cmd)
 
     PushCalcEntry(entryBox);
 
-    if (op != NULL) {
+    if ((!ErrorRaised()) &&
+        (op != NULL)) {
         op->execute();
     }
+
+    ErrorRaised();
     
     UpdateStack();
 }
@@ -316,7 +333,13 @@ void HandleOpClick(void)
         if (op != NULL) {
             CtlRecHndl entryBox = GetCtlHandleFromID(gCalcWinPtr, abCalcEntryBox);
             PushCalcEntry(entryBox);
-            op->execute();
+
+            if (!ErrorRaised()) {
+                op->execute();
+            }
+
+            ErrorRaised();
+
             UpdateStack();
         }
 
@@ -373,6 +396,7 @@ void HandleControl(EventRecord *event)
 
         case abCalcBtnEnter:
             PushCalcEntry(entryBox);
+            ErrorRaised();
             UpdateStack();
             break;
 
diff --git a/abCalcNDA.defs b/abCalcNDA.defs
index c3caeff..b383cc6 100644
--- a/abCalcNDA.defs
+++ b/abCalcNDA.defs
@@ -81,9 +81,11 @@
 #define abCalcBtnPow    2047
 #define abCalcBtnPowStr 2048
 
-#define abCalcEntryBox 2049
-#define abCalcStackList 2050
-#define abCalcOpList 2051
+#define abCalcEntryBox 3001
+#define abCalcStackList 3002
+#define abCalcOpList 3003
+
+#define abCalcErrorAlert 4001
 
 
 #define abCalcWinX 10
diff --git a/abCalcNDA.rez b/abCalcNDA.rez
index a98afbc..7c7baa1 100644
--- a/abCalcNDA.rez
+++ b/abCalcNDA.rez
@@ -453,3 +453,10 @@ resource rControlTemplate (abCalcEntryBox) {
       0                                 /* text Ref */
       }};
    };
+
+resource rAlertString (abCalcErrorAlert) {
+    "23/"
+    "*0"
+    "/^#0\$00"
+};
+
diff --git a/ops/abCOp.c b/ops/abCOp.c
index dd406ed..550895a 100644
--- a/ops/abCOp.c
+++ b/ops/abCOp.c
@@ -72,6 +72,7 @@ static int gNumOps = 0;
 
 void abCalcOpInit(void)
 {
+    gNumOps = 0;
     memset(gOps, 0, sizeof(gOps));
 
     abCalcOpAddInit();