[exim] Referring people to the docs vs. an example

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Author: Marc Perkel
Date:  
To: Peter Bowyer
CC: exim users
Old-Topics: Re: [exim] connection defer depending on load average
Subject: [exim] Referring people to the docs vs. an example


Peter Bowyer wrote:
> On 17/07/07, Marc Perkel <marc@???> wrote:
>
>
>
>> Ir's easier to just answer the question than just point someone to the docs.
>>
>
> Referring to the docs is *always* an acceptable answer, when done in a
> helpful way (as it was here).
>
> A lazy way to answer the question would be to just quote a sample line
> of config. A more helpful way is to point the OP to the right place in
> the docs where he can read about what's being proposed, along with all
> the other useful stuff to be found there. Then he might be able to
> answer his next question himself.
>
> This only applies to people prepared to read for themselves, of
> course. The rest will keep coming back here with questions that could
> be answered with a trivial search of the documentation.
>
> Peter
>
>


Although pointing t the docs is helpful and Exim docs are better than
most open source projects, the Exim scripting is not very intuitive and
has a lot of quirks and is light on examples. So even if you go to the
docs for someone who is new to Exim they will still spend an hour trying
to do something simple.

In this example, the user asked about how to do something based on load
levels. Yes, Exim has a $load_average command but you also have to be
aware that you have to use 1000x for your comparison because Exim
doesn't take floating point numbers, (40.0 would be more intuitive that
40000). And you have to be able to build an Exim conditional, which is
not intuitive at all.

defer condition = ${if > {$load_average}{40000}{true}{false}}

No other language that I know of builds conditionals that look like
this. So if you are a new user then you also have to research how to
build a conditional comparison. And you also have to understand the
whole ACL thing. But if you just actually answer the question then the
person can paste the code into the ACL without having to spend hours
looking up several things that some of us just know. Most people don't
dedicate their lives to Exim.

On that subject, Exim syntax is it's weakest feature. It is only good if
you compare it to Sendmail which looks like modem noise. It would be a
far mor productive language if it were more pascal like:

if $load_average > 40 then defer

So - pointing to the docs might be barely good enough but pasting a bit
of code example is generally better.