// glBufferStorage
{
    GLuint buf;
    glGenBuffers(1, &buf);
    glBindBuffer(GL_ARRAY_BUFFER, buf);
    glBufferStorage(GL_ARRAY_BUFFER, 20, null, GL_DYNAMIC_STORAGE_BIT);

    GLint size;
    glGetNamedBufferParameteriv(buf, GL_BUFFER_SIZE, &size);
    writeln(size); // prints 20
}

// glNamedBufferStorage
{
    GLuint buf;
    glGenBuffers(1, &buf);
    glNamedBufferStorage(buf, 20, null, GL_DYNAMIC_STORAGE_BIT); // 1282 GL_INVALID_OPERATION error generated. <buffer> does not refer to an existing buffer object.

    GLint size;
    glGetNamedBufferParameteriv(buf, GL_BUFFER_SIZE, &size); // 1282 GL_INVALID_OPERATION error generated. <buffer> does not refer to an existing buffer object.
    writeln(size); // prints 0
}