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Codes / Error Code 015

Error Code 015

Overview

This error occurs when attempting to perform a type cast that is either unsupported or unsafe. It can happen when trying to cast incompatible types or when the cast results in undefined behavior.

Details

  • Common Causes:

    • Casting between unrelated or incompatible types.
    • Casting a base class to a derived class without proper inheritance.
    • Unsafe pointer casts that lead to runtime errors.

  • Example:

void main() {
    void* ptr = null;
    int* intPtr = cast(int*) ptr; // Error: invalid cast
}
  • Solution:
    • Ensure the cast is valid by verifying type compatibility: 
      void main() {
    void* ptr = cast(void*) malloc(int.sizeof);
    int* intPtr = cast(int*) ptr; // Valid cast
    free(ptr);
}
    • Use dynamic casts for safe runtime type checking: 
      class Base {}
class Derived : Base {}

void main() {
    Base obj = new Base();
    auto derivedObj = cast(Derived) obj; // Returns null if invalid
}
    • Avoid unnecessary or unsafe casts by designing code with proper type constraints.