Don’t write unintentionally nongeneric code

Commit to abstractions, not to details. Use the most generic and abstract means to implement a piece of functionality. More generic code is more reusable and more resilient to changes in its surroundings.

Some examples:

• Use empty() instead of size() == 0

• Write const-correct code using const& parameters

• Prefer iteration to indexed access

• Use the highest class in the hierarchy that offers what you need

Exceptions:

Sometimes indexing is faster, but check before you blindly do it.