update

src/mini_safe_array/mini_safe_array.cpp

@@ -0,0 +1,91 @@
+#include <algorithm>
+#include <initializer_list>
+#include <iostream>
+#include <sstream>
+#include <stdexcept>
+#include <string>
+#include <type_traits>
+#include <utility>
+
+using ll = long long;
+#define NVF(v)#v," : ",(v)
+
+template<class ...Args>
+std::string fmt(Args&&...args){
+    std::ostringstream oss;
+    (oss<<...<<std::forward<Args>(args));
+    return std::string(oss.str());
+}
+
+template<class ...Args>
+void print(Args&&...args){
+    std::ostringstream oss;
+    (oss<<...<<std::forward<Args>(args));
+    std::cout<<oss.str();
+}
+
+// #define NDEBUG
+#ifdef NDEBUG
+    #define NDB_NOEXCEPT noexcept
+#else
+    #define NDB_NOEXCEPT
+#endif
+
+template<class T, ll _size>//size_t
+class SafeArray{
+    T arr[_size];
+public:
+    constexpr SafeArray()NDB_NOEXCEPT{};
+    constexpr SafeArray(const std::initializer_list<T> init)NDB_NOEXCEPT:arr{}{
+        #ifndef NDEBUG
+            if(!std::is_constant_evaluated())[[unlikely]]{
+                if(init.size()>_size){
+                    throw std::runtime_error(fmt("std::initializer _size error when constructing SafeArray\n",
+                                                "in ",__PRETTY_FUNCTION__," \n",
+                                                "initialize_list should < ",_size,"\n"
+                                                "but your initialize_list.size is ",init.size(),"\n"));
+                }
+            }
+        #endif
+        std::copy(init.begin(),init.end(),arr);
+    }
+    constexpr ll size()const noexcept{
+        return size;
+    }
+    constexpr T& operator[](const ll index)NDB_NOEXCEPT{
+        #ifndef NDEBUG
+            if(!std::is_constant_evaluated()){
+                if(!(0<=index&&index<_size))[[unlikely]]{
+                    throw std::runtime_error(fmt("in ",__PRETTY_FUNCTION__," error!\n",
+                                                "0 <= index < ",_size,'\n',
+                                                "but your index is : ",index,"\n"));
+                }
+            }
+        #endif
+        return arr[index];
+    }
+    constexpr const T& operator[](const ll index)const NDB_NOEXCEPT{
+        #ifndef NDEBUG
+            if(!std::is_constant_evaluated()){
+                if(!(0<=index&&index<_size))[[unlikely]]{
+                    throw std::runtime_error(fmt("in ",__PRETTY_FUNCTION__," error!\n",
+                                                "0 <= index < ",_size,'\n',
+                                                "but your index is :",index,"\n"));
+                }
+            }
+        #endif
+        return arr[index];
+    }
+};
+
+int main(){
+    // const int *const p = new int;
+    // p = new int;
+
+    constexpr SafeArray<ll, 5> arr{1,2,3,4,5};
+    SafeArray<ll, 5> arr1{0,1,2,3,4};
+    arr1[4]=5;
+    arr[-1];
+    print(NVF(arr[4]),'\n',
+            NVF(arr[5]),'\n');
+}