diff --git a/src/nrniv/secbrows.cpp b/src/nrniv/secbrows.cpp
index 84263229b6..207a5b6b4f 100644
--- a/src/nrniv/secbrows.cpp
+++ b/src/nrniv/secbrows.cpp
@@ -121,17 +121,13 @@ OcSectionBrowser::OcSectionBrowser(Object* ob)
             psec_[scnt_++] = sec;
         }
     } else {
-        struct hoc_Item* qsec;
         scnt_ = 0;
-        // ForAllSections(sec)  //{
-        ITERATE(qsec, section_list) {
+        for (const Section* sec: range_sec(section_list)) {
             ++scnt_;
         }
         psec_ = new Section*[scnt_];
         scnt_ = 0;
-        // ForAllSections(sec)  //{
-        ITERATE(qsec, section_list) {
-            Section* sec = hocSEC(qsec);
+        for (Section* sec: range_sec(section_list)) {
             psec_[scnt_++] = sec;
         }
     }
@@ -359,18 +355,13 @@ void BrowserAccept::execute() {
 }
 
 SectionBrowserImpl::SectionBrowserImpl() {
-    struct hoc_Item* qsec;
     scnt_ = 0;
-    // ForAllSections(sec)  //{
-    ITERATE(qsec, section_list) {
-        Section* sec = hocSEC(qsec);
+    for (const Section* sec: range_sec(section_list)) {
         ++scnt_;
     }
     psec_ = new Section*[scnt_];
     scnt_ = 0;
-    // ForAllSections(sec)  //{
-    ITERATE(qsec, section_list) {
-        Section* sec = hocSEC(qsec);
+    for (Section* sec: range_sec(section_list)) {
         psec_[scnt_++] = sec;
         section_ref(sec);
     }
diff --git a/src/nrnoc/cabcode.cpp b/src/nrnoc/cabcode.cpp
index fe6de4e3a2..85c4b1b392 100644
--- a/src/nrnoc/cabcode.cpp
+++ b/src/nrnoc/cabcode.cpp
@@ -450,10 +450,7 @@ Section* chk_access() {
     Section* sec = secstack[isecstack];
     if (!sec || !sec->prop) {
         /* use any existing section as a default section */
-        hoc_Item* qsec;
-        // ForAllSections(lsec)
-        ITERATE(qsec, section_list) {
-            Section* lsec = hocSEC(qsec);
+        for (Section* lsec: range_sec(section_list)) {
             if (lsec->prop) {
                 sec = lsec;
                 ++sec->refcount;
@@ -479,10 +476,7 @@ Section* nrn_noerr_access(void) /* return 0 if no accessed section */
     Section* sec = secstack[isecstack];
     if (!sec || !sec->prop) {
         /* use any existing section as a default section */
-        hoc_Item* qsec;
-        // ForAllSections(lsec)
-        ITERATE(qsec, section_list) {
-            Section* lsec = hocSEC(qsec);
+        for (Section* lsec: range_sec(section_list)) {
             if (lsec->prop) {
                 sec = lsec;
                 ++sec->refcount;
@@ -1639,8 +1633,6 @@ void nrn_parent_info(Section* s) {
 }
 
 void setup_topology(void) {
-    Item* qsec;
-
     /* use connection info in section property to connect nodes. */
     /* for the moment we assume uniform dx and range 0-1 */
 
@@ -1656,9 +1648,7 @@ void setup_topology(void) {
 
     nrn_global_ncell = 0;
 
-    // ForAllSections(sec)
-    ITERATE(qsec, section_list) {
-        Section* sec = hocSEC(qsec);
+    for (Section* sec: range_sec(section_list)) {
 #if 0
 		if (sec->nnode < 1) { /* last node is not a segment */
 			hoc_execerror(secname(sec),
@@ -2200,15 +2190,11 @@ void hoc_level_pushsec(Section* sec) {
 }
 
 void push_section(void) {
-    Section* sec;
+    Section* sec = nullptr;
     if (hoc_is_str_arg(1)) {
-        Item* qsec;
         char* s;
-        sec = (Section*) 0;
         s = gargstr(1);
-        // ForAllSections(sec1) /* I can't imagine a more inefficient way */
-        ITERATE(qsec, section_list) {
-            Section* sec1 = hocSEC(qsec);
+        for (Section* sec1: range_sec(section_list)) {
             if (strcmp(s, nrn_sec2pysecname(sec1)) == 0) {
                 sec = sec1;
                 break;
diff --git a/src/nrnoc/extcelln.cpp b/src/nrnoc/extcelln.cpp
index d807f2bf47..ccfc4250a1 100644
--- a/src/nrnoc/extcelln.cpp
+++ b/src/nrnoc/extcelln.cpp
@@ -225,9 +225,7 @@ void extnode_free_elements(Extnode* nde) {
 }
 
 static void check_if_extracellular_in_use() {
-    hoc_Item* qsec;
-    ITERATE(qsec, section_list) {
-        Section* sec = hocSEC(qsec);
+    for (const Section* sec: range_sec(section_list)) {
         if (sec->pnode[0]->extnode) {
             hoc_execerror("Cannot change nlayer_extracellular when instances exist", NULL);
         }
@@ -486,14 +484,11 @@ void ext_con_coef(void) /* setup a and b */
 {
     int j, k;
     double dx, area;
-    hoc_Item* qsec;
     Node *nd, **pnd;
     Extnode* nde;
 
     /* temporarily store half segment resistances in rhs */
-    // ForAllSections(sec)
-    ITERATE(qsec, section_list) {
-        Section* sec = hocSEC(qsec);
+    for (Section* sec: range_sec(section_list)) {
         if (sec->pnode[0]->extnode) {
             dx = section_length(sec) / ((double) (sec->nnode - 1));
             for (j = 0; j < sec->nnode - 1; j++) {
@@ -529,9 +524,7 @@ void ext_con_coef(void) /* setup a and b */
     section connects straight to the point*/
     /* for the near future we always have a last node at x=1 with
     no properties */
-    // ForAllSections(sec)
-    ITERATE(qsec, section_list) {
-        Section* sec = hocSEC(qsec);
+    for (const Section* sec: range_sec(section_list)) {
         if (sec->pnode[0]->extnode) {
             /* node half resistances in general get added to the
             node and to the node's "child node in the same section".
@@ -549,9 +542,7 @@ void ext_con_coef(void) /* setup a and b */
             }
         }
     }
-    // ForAllSections(sec)
-    ITERATE(qsec, section_list) {
-        Section* sec = hocSEC(qsec);
+    for (Section* sec: range_sec(section_list)) {
         if (sec->pnode[0]->extnode) {
             /* convert to siemens/cm^2 for all nodes except last
             and microsiemens for last.  This means that a*V = mamps/cm2
@@ -578,9 +569,7 @@ void ext_con_coef(void) /* setup a and b */
         }
     }
     /* now the effect of parent on node equation. */
-    // ForAllSections(sec)
-    ITERATE(qsec, section_list) {
-        Section* sec = hocSEC(qsec);
+    for (const Section* sec: range_sec(section_list)) {
         if (sec->pnode[0]->extnode) {
             for (j = 0; j < sec->nnode; j++) {
                 nd = sec->pnode[j];
diff --git a/src/nrnoc/solve.cpp b/src/nrnoc/solve.cpp
index a3e55c2535..a42fbe960a 100644
--- a/src/nrnoc/solve.cpp
+++ b/src/nrnoc/solve.cpp
@@ -100,17 +100,13 @@ Section** secorder;
 double debugsolve(void) /* returns solution error */
 {
     short inode;
-    int i;
-    Section *sec, *psec, *ch;
     Node *nd, *pnd, **ndP;
     double err, sum;
 
     /* save parts of matrix that will be destroyed */
-    assert(0)
-        /* need to save the rootnodes too */
-        // ForAllSections(sec)
-        ITERATE(qsec, section_list) {
-        Section* sec = hocSEC(qsec);
+    assert(0);
+    /* need to save the rootnodes too */
+    for (const Section* sec: range_sec(section_list)) {
         assert(sec->pnode && sec->nnode);
         for (inode = sec->nnode - 1; inode >= 0; inode--) {
             nd = sec->pnode[inode];
@@ -124,9 +120,7 @@ double debugsolve(void) /* returns solution error */
 
     err = 0.;
     /* need to check the rootnodes too */
-    // ForAllSections(sec)
-    ITERATE(qsec, section_list) {
-        Section* sec = hocSEC(qsec);
+    for (const Section* sec: range_sec(section_list)) {
         for (inode = sec->nnode - 1; inode >= 0; inode--) {
             ndP = sec->pnode + inode;
             nd = sec->pnode[inode];
@@ -141,10 +135,9 @@ double debugsolve(void) /* returns solution error */
             if (inode < sec->nnode - 1) {
                 sum += NODEA(ndP[1]) * NODERHS(ndP[1]);
             }
-            for (ch = nd->child; ch; ch = ch->sibling) {
-                psec = ch;
-                pnd = psec->pnode[0];
-                assert(pnd && psec->nnode);
+            for (const Section* ch = nd->child; ch; ch = ch->sibling) {
+                pnd = ch->pnode[0];
+                assert(pnd && ch->nnode);
                 sum += NODEA(pnd) * NODERHS(pnd);
             }
             sum -= nd->savrhs;
@@ -291,12 +284,9 @@ static void dashes(Section* sec, int offset, int first);
 
 void nrnhoc_topology(void) /* print the topology of the branched cable */
 {
-    hoc_Item* q;
-
     v_setup_vectors();
     Printf("\n");
-    ITERATE(q, section_list) {
-        Section* sec = (Section*) VOIDITM(q);
+    for (Section* sec: range_sec(section_list)) {
         if (sec->parentsec == (Section*) 0) {
             Printf("|");
             dashes(sec, 0, '-');
@@ -434,10 +424,7 @@ void bksub(NrnThread* _nt) {
 }
 
 void nrn_clear_mark(void) {
-    hoc_Item* qsec;
-    // ForAllSections(sec)
-    ITERATE(qsec, section_list) {
-        Section* sec = hocSEC(qsec);
+    for (Section* sec: range_sec(section_list)) {
         sec->volatile_mark = 0;
     }
 }
@@ -744,15 +731,10 @@ void section_order(void) /* create a section order consistent */
 {
     int order, isec;
     Section* ch;
-    Section* sec;
-    hoc_Item* qsec;
 
     /* count the sections */
     section_count = 0;
-    /*SUPPRESS 765*/
-    // ForAllSections(sec)
-    ITERATE(qsec, section_list) {
-        Section* sec = hocSEC(qsec);
+    for (Section* sec: range_sec(section_list)) {
         sec->order = -1;
         ++section_count;
     }
@@ -765,9 +747,7 @@ void section_order(void) /* create a section order consistent */
         secorder = (Section**) emalloc(section_count * sizeof(Section*));
     }
     order = 0;
-    // ForAllSections(sec) /* all the roots first */
-    ITERATE(qsec, section_list) {
-        Section* sec = hocSEC(qsec);
+    for (Section* sec: range_sec(section_list)) {
         if (!sec->parentsec) {
             secorder[order] = sec;
             sec->order = order;
@@ -777,10 +757,7 @@ void section_order(void) /* create a section order consistent */
 
     for (isec = 0; isec < section_count; isec++) {
         if (isec >= order) {
-            // Sections form a loop.
-            // ForAllSections(sec)
-            ITERATE(qsec, section_list) {
-                Section* sec = hocSEC(qsec);
+            for (Section* sec: range_sec(section_list)) {
                 Section *psec, *s = sec;
                 for (psec = sec->parentsec; psec; s = psec, psec = psec->parentsec) {
                     if (!psec || s->order >= 0) {
@@ -798,7 +775,7 @@ void section_order(void) /* create a section order consistent */
                 }
             }
         }
-        sec = secorder[isec];
+        Section* sec = secorder[isec];
         for (ch = sec->child; ch; ch = ch->sibling) {
             secorder[order] = ch;
             ch->order = order;
diff --git a/src/nrnoc/treeset.cpp b/src/nrnoc/treeset.cpp
index f27b02fa4f..e7fc5c78c0 100644
--- a/src/nrnoc/treeset.cpp
+++ b/src/nrnoc/treeset.cpp
@@ -814,7 +814,6 @@ void connection_coef(void) /* setup a and b */
 {
     int j;
     double area;
-    hoc_Item* qsec;
     Node* nd;
 #if RA_WARNING
     extern int nrn_ra_set;
@@ -836,9 +835,7 @@ void connection_coef(void) /* setup a and b */
 #endif
     ++recalc_diam_count_;
     nrn_area_ri_nocount_ = 1;
-    // ForAllSections(sec)
-    ITERATE(qsec, section_list) {
-        Section* sec = hocSEC(qsec);
+    for (Section* sec: range_sec(section_list)) {
         nrn_area_ri(sec);
     }
     nrn_area_ri_nocount_ = 0;
@@ -858,9 +855,7 @@ void connection_coef(void) /* setup a and b */
         std::fill_n(nt.node_a_storage(), nt.end, 0.0);
         std::fill_n(nt.node_b_storage(), nt.end, 0.0);
     }
-    // ForAllSections(sec)
-    ITERATE(qsec, section_list) {
-        Section* sec = hocSEC(qsec);
+    for (Section* sec: range_sec(section_list)) {
         // Unnecessary because they are unused, but help when looking at fmatrix.
         if (!sec->parentsec) {
             if (auto* const ptr = nrn_classicalNodeA(sec->parentnode)) {
@@ -889,9 +884,7 @@ void connection_coef(void) /* setup a and b */
         }
     }
     /* now the effect of parent on node equation. */
-    // ForAllSections(sec)
-    ITERATE(qsec, section_list) {
-        Section* sec = hocSEC(qsec);
+    for (const Section* sec: range_sec(section_list)) {
         for (j = 0; j < sec->nnode; j++) {
             nd = sec->pnode[j];
             *nrn_classicalNodeB(nd) = -1.e2 * NODERINV(nd) / NODEAREA(nd);
diff --git a/src/oc/hoclist.h b/src/oc/hoclist.h
index de9666efa0..3a7036dadc 100644
--- a/src/oc/hoclist.h
+++ b/src/oc/hoclist.h
@@ -47,8 +47,33 @@ struct hoc_Item {
 };
 using hoc_List = hoc_Item;
 
-#define ITEM0 (hoc_Item*) 0
-#define LIST0 (hoc_List*) 0
+constexpr auto range_sec(hoc_List* iterable) {
+    struct iterator {
+        hoc_Item* iter;
+        bool operator!=(const iterator& other) const {
+            return iter != other.iter;
+        }
+        void operator++() {
+            iter = iter->next;
+        }
+        Section* operator*() const {
+            return iter->element.sec;
+        }
+    };
+    struct iterable_wrapper {
+        hoc_List* iterable;
+        auto begin() {
+            return iterator{iterable->next};
+        }
+        auto end() {
+            return iterator{iterable};
+        }
+    };
+    return iterable_wrapper{iterable};
+}
+
+#define ITEM0 nullptr
+#define LIST0 nullptr
 
 #define ITERATE(itm, lst) for (itm = (lst)->next; itm != (lst); itm = itm->next)
 /*