Tempodivalse:Or: Kiom da fromaĝburgeroj vi manĝis dum via vivo?

That too.

eshapard:I was thinking about it later and realized that I'd probably think of cxiam as being 'each time'. So I might think you were asking how many cheeseburgers I ate each time I ate a cheeseburger (one, I guess).

(Yes, hopefully not much more than one )

eshapard:
Maybe ankoraŭ is a better option. Jam would work too, I think. Either word expresses the idea of 'up until now', right?

Kiom da fromaĝburgeroj vi manĝis ankoraŭ? (or does that sound weird?)

"Kiom da fromaĝburgeroj vi manĝis ankoraŭ?" I would understand as "How many more cheeseburgers have you eaten?". With "jam" it would be "How many have you eaten already?". So, still no indications of an all-time total.

eshapard:
Translation dictionaries seem to define cxiam as 'always, ever'. It definitely can be used to mean ever when ever and always mean the same thing (ever vigilant, forever, ever-ready); kind of an older usage, I guess.

Good point. Somehow those didn't come to mind.

eshapard:Then there's always the participle route: Kiom da fromagxbergeroj, vi estas mangxinta?

Which would still convey the idea of "how many have you eaten/did you eat?", just in a more awkward-sounding way.

eshapard:I don't have a handle on the difference between ankoraux and jam in some circumstances. They have some distinct usages (still vs already), but there seems to be some overlap (both mean yet). Any pointers?

Actually I can't think of any example where "jam" could mean "yet". I even made sure of it by going over the example sentences of "yet" in the Cambridge dictionary and translating them (corrections are welcome, should the case arise):

I haven't spoken to her yet. -> Mi ankoraŭ ne parolis kun ŝi.

Of all the songs I've heard tonight, that's the best yet. -> El ĉiuj la kantoj, kiujn mi aŭdis ĉi-nokte, tiu estas ĝis nun la plej bona.

We haven't needed extra staff as yet, but may do in the future. -> Ni ankoraŭ ne bezonis plian personaron ĝis nun, sed povus estonte.

He won't be back for a long time yet. -> Li ne revenos antaŭ longe.

They have yet to make a decision. -> Ili ankoraŭ devas fari decidon.

We could yet succeed - you never know. -> Ni (tamen) (eĉ nun) ankoraŭ povus sukcesi - oni neniam scias.

I'm sorry to bother you yet again. -> Mi bedaŭras ĝeni vin refoje/ankoraŭ.

simple yet effective -> simpla, tamen efika

eshapard:
I don't have a handle on the difference between ankoraux and jam in some circumstances. They have some distinct usages (still vs already), but there seems to be some overlap (both mean yet). Any pointers?

After poking around on vortaro.net, I think I can answer my own question.

Ankoraŭ:

• still
  
• yet when it means pretty much the same as still (ju pli mi lernas, des pli mi vidas, ke mi devas ankoraŭ lerni - the more I learn, the more I see that I must still learn)
  
• yet (when used with another): li sonĝis ankoraŭ alian sonĝon - he dreamed yet another dream.

Jam:

• Already
  
• Before some time/now: se li jam venis, petu lin al mi (if he has come, bid him [come] to me. ???)

Looks like jam can be used to indicate 'before now', but ankoraŭ only means 'still', or 'yet/still [another]'.

yyaann:

eshapard:Then there's always the participle route: Kiom da fromagxbergeroj, vi estas mangxinta?

Which would still convey the idea of "how many have you eaten/did you eat?", just in a more awkward-sounding way.

'Have eaten' is exactly what I'm after! In English, 'have eaten' has no time constraint unless context makes one clear. So how many cheeseburgers have you eaten, or how many Frenchmen have you met imply ...in your entire life up to now (ever).

But, at least in English, how many did you eat tends to imply that we're talking about a certain time... how many yesterday, how many three days ago, how many when you went to France, etc.

If someone asked me how many cheeseburgers I've eaten, I'd tell them that I couldn't possibly count them all. If someone asked how many I ate, I'd ask when?

Perhaps the Esperanto equivalents manĝis (ate) and estas manĝinta (have eaten) don't work the same way. Maybe my knowledge of English is getting in the way.

For practical purposes, Esperanto lacks the built-in distinction between simple past and preterit/perfect. So: "How many cheeseburgers have you eaten?" and "How many cheeseburgers did you eat?" both translate the same way, using manĝis.

It sounds contrived to say estas manĝinta - or to use an active compound tense in almost any context, even if this would be done in English. Try not to model Esperanto on English too much here, they're quite different, even if technically you can replicate the English verbs.

Esperanto verbs simply don't demand the same level of detail as English ones. Slavic languages (minus Bulgarian/Macedonian) work in much the same way, as do Chinese and Malay/Indonesian, among others. English is rather the outlier here, due to its complex verb system.

If you need to make some time distinction for clarity, it is normally better to use helping words like jam, antaue, ankorau etc. to help the reader/listener understand the proper sequence of events.

For practical purposes, Esperanto lacks the built-in distinction between simple past and preterit/perfect. So: "How many cheeseburgers have you eaten?" and "How many cheeseburgers did you eat?" both translate the same way, using manĝis.

It sounds contrived to say estas manĝinta - or to use an active compound tense in almost any context

Of course, you are right to say that the simple past form might be translated into English as either have X-ed or X-ed, depending on the particular context.

But the compound form estas x-inta has been used in Esperanto right from the beginning to the present day.

A nice example from Zamenof is : vintre kiam la tero estas glaciiĝinta which is not quite the same as vintre kiam la tero glaciiĝis.

Nor is kiam vi faros tion, ... (when you do that) the same as kiam vi estos farinta tion, ... (when you have done that).

If you look through the occurrences in the Tekstaro you will find some cases where the simple form would do just as well - Ĉu ni jam estas alvenintaj en Parizo? li sin demandis; here Ĉu ni jam alvenis en Parizo? li sin demandis would seem to be just as good.

The rule about the active compound forms (int/ant) is not shun them completely, but use them when you need to (which is much less frequently than you might expect as an English speaker). So, when the simple form would plausibly not convey the intended meaning, or you wish to emphasize the 'int-eco'/'ant-eco'.

In any case if you overuse them you won't be misunderstood, nor will you be committing a grammatical error.

I wonder whether the thrust of the OP's post was not concerned with the cases when you would naturally use 'jam' or 'iam' to translate English's present perfect.

The present perfect is used in English for unfinished time - a period up till now. This period (ĝis nun) can be short (the recent past) or long (many years). The present perfect per se does not tell us what period of time the speaker has in mind.

Have you seen my car keys? doesn't ask whether you have ever seen them.

So Ĉu vi iam vidis la ŝlosilojn de mia aŭto would not be the appropriate translation, nor would Ĉu vi jam vidis miajn ŝlosilojn.

We may need to add in a 'jam' ensure that meaning of the English present perfect is preserved, when the simple past alone could be misinterpreted.

Have you met Mr. Jones - Ĉu vi jam renkontis S-ron Jones.

In short sometimes no qualifier will be required, sometimes 'iam' will be needed to imply at any time not just recently, sometimes 'jam' to preserve the 'has happened' aspect.

It all depends on what the Esperanto verb in its simple form alone could mean in that particular sentence in that particular context.

Basically, from an English point of view, the Esperanto simple past has multiple meanings.

Sudanglo, perhaps I should have said that you shouldn't use compound active tenses unless it is essential to convey a particular nuance. For me, in practice (and for most proficient speakers I observe), this still amounts to a small minority of cases.

I also have observed a pattern of English speakers overthinking the verb system, which is why I try to downplay it.

So if you're a beginner and you're unsure in a particular instance whether to use compound or simple active, chances are that simple is better. Sudanglo's correct that it's not grammatically wrong or unintelligible to use the compounds, but I might add that it's usually not wrong to use the simple even if it were stylistically preferable to use a compound. English speakers seem hesitant to rely on context, but context will often clear things up.

Nor is kiam vi faros tion, ... (when you do that) the same as kiam vi estos farinta tion, ... (when you have done that).

The latter is more explicit, sure. But it seems you would still be understood by context if you were to use the former to express the latter.

Though I would have preferred to say Post kiam vi faros tion... or Farinte tion, vi + future - but maybe that's my Slavic background ...

vintre kiam la tero estas glaciiĝinta which is not quite the same as vintre kiam la tero glaciiĝis.

Good example! Though I would be tempted to say that kiam la tero glaciiĝas conveys a somewhat similar meaning.

Tempodivalse:

vintre kiam la tero estas glaciiĝinta which is not quite the same as vintre kiam la tero glaciiĝis.

Good example! Though I would be tempted to say that kiam la tero glaciiĝas conveys a somewhat similar meaning.

No doubt that -int- is used to express anteriority. However, could you show use some examples (pref. Zamenhovian) where "estas X'anta" means something different to "X'as"?

Only "present continuous" used by Zamenhof I could find is this one:

LLZ:Oni povus diri, ke ŝi estas finanta interparoladon kun sia propra interno kaj ŝi intencas nun diri la lastan vorton de tiu interparolado, vorton, esprimontan ian tre malfacile atingitan decidon.

And I guess it means something like "she is now busy finishing the conversation" or something like that.