Assignments in the middle of expressions is legal in LSL, but not in Lua. Bump that problem until later.

2 files changed, 38 insertions, 1 deletions

diff --git a/LuaSL/Test sim/objects/onefang's test bed/~menucfg.lsl b/LuaSL/Test sim/objects/onefang's test bed/~menucfg.lsl
index d38843d..a258fb8 100644
--- a/LuaSL/Test sim/objects/onefang's test bed/~menucfg.lsl
+++ b/LuaSL/Test sim/objects/onefang's test bed/~menucfg.lsl
@@ -254,10 +254,12 @@ state load {
 
         integer ix;
         integer count;
-        while ((ix = myListFind(buttons, "-")) != -1) {
+        ix = myListFind(buttons, "-");
+        while (ix != -1) {
             ++count;
             buttons = llDeleteSubList(buttons, ix, ix);
             commands = llDeleteSubList(commands, ix, ix);
+            ix = myListFind(buttons, "-");
         }
         if (count) {
             for (ix = 1; ix < llGetListLength(buttonindex); ++ix) {
diff --git a/LuaSL/src/LuaSL_compile.c b/LuaSL/src/LuaSL_compile.c
index e9a22c1..8194947 100644
--- a/LuaSL/src/LuaSL_compile.c
+++ b/LuaSL/src/LuaSL_compile.c
@@ -1,5 +1,40 @@
 #include "LuaSL.h"
 
+/* TODO - 
+
+Assignments in the middle of expressions is legal in LSL, but not in Lua.
+The big complication is that they often happen in the conditionals of flow control statements.  That's a big bitch.
+
+So things like -
+
+    while ((x = doSomething()) == foo)
+    {
+        buggerAround();
+    }
+
+Turns into - 
+
+    x = doSomething();
+    while (x == foo)
+    {
+        buggerAround();
+        x = doSomething();
+    }
+
+http://lua-users.org/wiki/StatementsInExpressions might be helpful.  Which suggests something like this -
+
+    while ( (function() x = doSomething(); return x; end)() == foo)
+    {
+        buggerAround();
+    }
+
+The remaining problem is when to recognise the need to do that.
+Note that assignments are really low precedence.
+    While adding operations
+        Flag the assignment expressions
+    If there is an assignment expression (not operation) on the RHS of an operation, we need to do this?
+*/
+
 
 static LSL_Leaf *evaluateFloatToken(LSL_Leaf  *content, LSL_Leaf *left, LSL_Leaf *right);
 static LSL_Leaf *evaluateIntegerToken(LSL_Leaf  *content, LSL_Leaf *left, LSL_Leaf *right);