From 4c953c91336c5aa37ec0631b6d71c1a6a2564e2a Mon Sep 17 00:00:00 2001
From: Matthew Fidler <matthew.fidler@gmail.com>
Date: Sun, 1 Dec 2024 20:06:25 -0600
Subject: [PATCH] Add dummyLhs bypass

---
 NEWS.md                  | 3 ++-
 src/genModelVars.h       | 2 +-
 src/parseCmtProperties.h | 9 +++++++++
 src/tran.c               | 1 +
 src/tran.h               | 1 +
 5 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/NEWS.md b/NEWS.md
index a4fea9384..3febe2b7e 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -2,7 +2,8 @@
 
 - Rework the `tad()` and related functions so they use the same
   interface as compartments (this way they do not depend on the order
-  of compartments); See #815
+  of compartments); See #815.  Also allow dummy variables to ignore
+  state requirements (for parsing mu-referenced equations).
 
 - Add `getRxNpars` to api.  This allows the development version of
   `babelmixr2` to better check what model is loaded and unload/reload
diff --git a/src/genModelVars.h b/src/genModelVars.h
index df76543fe..60efbbc4f 100644
--- a/src/genModelVars.h
+++ b/src/genModelVars.h
@@ -200,7 +200,7 @@ static inline SEXP calcIniVals(void) {
 SEXP orderForderS1(SEXP ordIn);
 
 static inline int sortStateVectorsErrHandle(int prop, int pass, int i) {
-  if (prop == 0 || pass == 1) {
+  if (prop == 0 || pass == 1 || tb.dummyLhs == 1) {
     return 1;
   }
   char *buf = NULL;
diff --git a/src/parseCmtProperties.h b/src/parseCmtProperties.h
index d333c043b..7bb3b4549 100644
--- a/src/parseCmtProperties.h
+++ b/src/parseCmtProperties.h
@@ -183,6 +183,9 @@ static inline int handleRemainingAssignmentsCalcPropComplexAssign(nodeInfo ni, c
       // New assignment
       tb.ixL = tb.ix;
       tb.lh[tb.ix] = isLHS;
+      if (!strcmp(v, "rxdummyLhs")) {
+        tb.dummyLhs = 1;
+      }
     } else if (tb.ix < 0){
       if (!strcmp("rxlin___", v)) {
         tb.ixL=-1;
@@ -216,6 +219,9 @@ static inline int handleRemainingAssignmentsCalcPropComplexAssign(nodeInfo ni, c
         tb.lh[tb.ix] = isLHSparam;
       } else {
         tb.lh[tb.ix] = isLHS;
+        if (!strcmp(v, "rxdummyLhs")) {
+          tb.dummyLhs = 1;
+        }
       }
       tb.ixL=-1;
     }
@@ -299,6 +305,9 @@ static inline int handleRemainingAssignmentsCalcPropIni(nodeInfo ni, char *name,
         /* Rprintf("Duplicate %s; %d %d\n", v, tb.lh[tb.ix], tb.ini0[tb.ix]); */
         if (tb.lh[tb.ix] != isLHS){
           tb.lh[tb.ix] = isLHS;
+          if (!strcmp(v, "rxdummyLhs")) {
+            tb.dummyLhs = 1;
+          }
           if (nodeHas(ini0) && tb.ini0[tb.ix] == 1){
             sPrint(&_gbuf,"cannot have conditional initial conditions for '%s'",v);
             updateSyntaxCol();
diff --git a/src/tran.c b/src/tran.c
index a79055839..641d33115 100644
--- a/src/tran.c
+++ b/src/tran.c
@@ -422,6 +422,7 @@ void reset(void) {
   tb.linExtra   = false;
   tb.nwhile     = 0;
   tb.lvlStr     = 0;
+  tb.dummyLhs   = 0;
   tb.nInd       = 0;
   tb.simflg     = 0;
   tb.nLlik      = 0;
diff --git a/src/tran.h b/src/tran.h
index 743886344..38819f336 100644
--- a/src/tran.h
+++ b/src/tran.h
@@ -107,6 +107,7 @@ lhs symbols?
   int lastDdt;
   int nLlik;
   int lvlStr;
+  int dummyLhs;
 } symtab;
 
 extern symtab tb;