Template Specialization

Template specialization lets you provide custom behavior for specific template arguments. Use it when the generic implementation is not correct or not optimal for a known type.

Full Specialization

Full specialization replaces the primary template for an exact type.

#include <iostream>

template <typename T>
struct Printer {
  static void print(const T& value) {
    std::cout << "generic: " << value << "\n";
  }
};

template <>
struct Printer<bool> {
  static void print(bool value) {
    std::cout << (value ? "true" : "false") << "\n";
  }
};

Partial Specialization

Partial specialization customizes only part of a template argument pattern.

#include <memory>

template <typename T>
struct TypeInfo {
  static constexpr const char* name = "value type";
};

template <typename T>
struct TypeInfo<T*> {
  static constexpr const char* name = "raw pointer";
};

template <typename T>
struct TypeInfo<std::unique_ptr<T>> {
  static constexpr const char* name = "unique pointer";
};

Guidelines

• Prefer overloads or concepts first when behavior differs by operation.
• Use specialization when behavior differs by type representation.
• Keep specializations close to the primary template for readability.

[!TIP] Full specialization matches one exact type. Partial specialization matches a family of types.