Manhattan SC guide doubt

[Meerak869]

Finally, the Present Perfect can be used in -ing forms, infinitives or subordinate clauses to clarify an
ambiguous sequence in time. For instance, the word when can mean either “at the same time” or “after.”

The use of Present Perfect resolves the meaning.

Right: She WILL PAY you when you ASK her. (No Present Perfect)
= She will pay you at the same time as you ask her, or maybe just after.

The above text is from Manhattan SC guide verb tense chapter.
I request you to indicate and explain the present perfect tense here as I feel this is in simple future tense.

[cgentry]

There is no present perfect in this example. This sentence is intended to indicate how a lack of present perfect tense implies that two events will occur simultaneously or almost simultaneously. My request, and her payment, will happen at the same time, or happen so close in time together that one could consider them simultaneous.

This is without present perfect.

When you introduce present perfect, you introduce a sequence of events that will not be simultaneous. Here's a present perfect example:

When I have written forum replies, I will eat dinner.

Compare that sentence to

When I write forum replies, I will eat dinner.

Which version says I'm eating right now, as I type this? Which version makes it clear that I'm going to finish typing this, then afterwards, fix myself some dinner?

[aflaamM589]

Meerak869: skip this post as i couldn't resist to answer : )

Which version says I'm eating right now, as I type this?

When I write forum replies, I will eat dinner.

Which version makes it clear that I'm going to finish typing this, then afterwards, fix myself some dinner?

When I have written forum replies, I will eat dinner.

Now where is my treat?

[cgentry]

Get yourself a cookie!