chore(library/init/string): remove string.iterator_imp

library/init/data/string/basic.lean

@@ -53,15 +53,10 @@ def fold {α} (a : α) (f : α → char → α) (s : string) : α :=
 s.to_list.foldl f a
 
 /- In the VM, the string iterator is implemented as a pointer to the string being iterated + index.
-
-   TODO: we currently cannot mark interator_imp as private because
-   we need to bind string_imp.mk and string_imp.cases_on in the VM.
--/
-structure iterator_imp :=
+   TODO: mark it opaque. -/
+structure iterator :=
 (fst : list char) (snd : list char)
 
-def iterator := iterator_imp
-
 def mk_iterator : string → iterator
 | ⟨s⟩ := ⟨[], s⟩
 

src/library/compiler/util.cpp

@@ -282,6 +282,7 @@ bool is_runtime_builtin_type(name const & n) {
     /* TODO(Leo): use an attribute? */
     return
         n == get_string_name() ||
+        n == get_string_iterator_name() ||
         n == get_uint8_name()  ||
         n == get_uint16_name() ||
         n == get_uint32_name() ||

src/library/constants.cpp

@@ -224,6 +224,7 @@ name const * g_sizeof = nullptr;
 name const * g_sorry_ax = nullptr;
 name const * g_string = nullptr;
 name const * g_string_empty = nullptr;
+name const * g_string_iterator = nullptr;
 name const * g_string_str = nullptr;
 name const * g_string_empty_ne_str = nullptr;
 name const * g_string_str_ne_empty = nullptr;
@@ -488,6 +489,7 @@ void initialize_constants() {
     g_sorry_ax = new name{"sorry_ax"};
     g_string = new name{"string"};
     g_string_empty = new name{"string", "empty"};
+    g_string_iterator = new name{"string", "iterator"};
     g_string_str = new name{"string", "str"};
     g_string_empty_ne_str = new name{"string", "empty_ne_str"};
     g_string_str_ne_empty = new name{"string", "str_ne_empty"};
@@ -753,6 +755,7 @@ void finalize_constants() {
     delete g_sorry_ax;
     delete g_string;
     delete g_string_empty;
+    delete g_string_iterator;
     delete g_string_str;
     delete g_string_empty_ne_str;
     delete g_string_str_ne_empty;
@@ -1017,6 +1020,7 @@ name const & get_sizeof_name() { return *g_sizeof; }
 name const & get_sorry_ax_name() { return *g_sorry_ax; }
 name const & get_string_name() { return *g_string; }
 name const & get_string_empty_name() { return *g_string_empty; }
+name const & get_string_iterator_name() { return *g_string_iterator; }
 name const & get_string_str_name() { return *g_string_str; }
 name const & get_string_empty_ne_str_name() { return *g_string_empty_ne_str; }
 name const & get_string_str_ne_empty_name() { return *g_string_str_ne_empty; }

src/library/constants.h

@@ -226,6 +226,7 @@ name const & get_sizeof_name();
 name const & get_sorry_ax_name();
 name const & get_string_name();
 name const & get_string_empty_name();
+name const & get_string_iterator_name();
 name const & get_string_str_name();
 name const & get_string_empty_ne_str_name();
 name const & get_string_str_ne_empty_name();

src/library/constants.txt

@@ -219,6 +219,7 @@ sizeof
 sorry_ax
 string
 string.empty
+string.iterator
 string.str
 string.empty_ne_str
 string.str_ne_empty

src/library/vm/vm_string.cpp

@@ -411,7 +411,7 @@ static pair<std::string, size_t> rev_list_as_string(vm_obj const & lst) {
     return mk_pair(s, len);
 }
 
-vm_obj string_iterator_imp_mk(vm_obj const & l1, vm_obj const & l2) {
+vm_obj string_iterator_mk(vm_obj const & l1, vm_obj const & l2) {
     pair<std::string, size_t> p1 = rev_list_as_string(l1);
     pair<std::string, size_t> p2 = list_as_string(l2);
     std::string s = p1.first;
@@ -421,7 +421,7 @@ vm_obj string_iterator_imp_mk(vm_obj const & l1, vm_obj const & l2) {
     return mk_vm_pair(new_s, mk_vm_nat(p1.second));
 }
 
-unsigned string_iterator_imp_cases_on(vm_obj const & o, buffer<vm_obj> & data) {
+unsigned string_iterator_cases_on(vm_obj const & o, buffer<vm_obj> & data) {
     vm_obj p = string_iterator_prev_to_string(o);
     vm_obj n = string_iterator_remaining_to_string(o);
     data.push_back(string_to_list_core(to_vm_string(p).m_value, true /* reverse */));
@@ -429,12 +429,12 @@ unsigned string_iterator_imp_cases_on(vm_obj const & o, buffer<vm_obj> & data) {
     return 0;
 }
 
-vm_obj string_iterator_imp_fst(vm_obj const & o) {
+vm_obj string_iterator_fst(vm_obj const & o) {
     vm_obj p = string_iterator_prev_to_string(o);
     return string_to_list_core(to_vm_string(p).m_value, true /* reverse */);
 }
 
-vm_obj string_iterator_imp_snd(vm_obj const & o) {
+vm_obj string_iterator_snd(vm_obj const & o) {
     vm_obj n = string_iterator_remaining_to_string(o);
     return string_to_list_core(to_vm_string(n).m_value);
 }
@@ -529,10 +529,10 @@ void initialize_vm_string() {
     DECLARE_VM_BUILTIN(name({"string", "iterator", "prev_to_string"}), string_iterator_prev_to_string);
     DECLARE_VM_BUILTIN(name({"string", "iterator", "extract"}),        string_iterator_extract);
 
-    DECLARE_VM_BUILTIN(name({"string", "iterator_imp", "mk"}),              string_iterator_imp_mk);
-    DECLARE_VM_BUILTIN(name({"string", "iterator_imp", "fst"}),             string_iterator_imp_fst);
-    DECLARE_VM_BUILTIN(name({"string", "iterator_imp", "snd"}),             string_iterator_imp_snd);
-    DECLARE_VM_CASES_BUILTIN(name({"string", "iterator_imp", "cases_on"}),  string_iterator_imp_cases_on);
+    DECLARE_VM_BUILTIN(name({"string", "iterator", "mk"}),              string_iterator_mk);
+    DECLARE_VM_BUILTIN(name({"string", "iterator", "fst"}),             string_iterator_fst);
+    DECLARE_VM_BUILTIN(name({"string", "iterator", "snd"}),             string_iterator_snd);
+    DECLARE_VM_CASES_BUILTIN(name({"string", "iterator", "cases_on"}),  string_iterator_cases_on);
 }
 
 void finalize_vm_string() {