Why some function are class-less?

[Stefan Koch via Digitalmars-d-learn]

On Thursday, 17 November 2016 at 17:54:23 UTC, Suliman wrote:
> On Thursday, 17 November 2016 at 17:45:31 UTC, Stefan Koch 
> wrote:
>> On Thursday, 17 November 2016 at 17:42:44 UTC, Suliman wrote:
>>> On Thursday, 17 November 2016 at 16:46:37 UTC, Steven 
>>> Schveighoffer wrote:
>>>> On 11/17/16 11:28 AM, Suliman wrote:
>>>>> [...]
>>>>
>>>> D does not require classes to write functions. All a class 
>>>> member function is anyway is a function with an implied 
>>>> class instance parameter.
>>>>
>>>> -Steve
>>>
>>> Ok, but what profit? Could you give me an example (for 
>>> example with logger)?
>>
>> for example writeln.
>> You would not want to create a stdio object just to call 
>> writeln.
>
> Ok, but when the logger class may be more helpful that function 
> usage?

If you log something you usually want to keep private state.
Classes are useful for that.