English translation:
so much…that
Structure
Verb + あまり
Verb[ た ] + あまり
なAdj + な + あまり
Noun・の + あまり
いAdj[ さ ]・の + あまり
Explanation:
[A あまり B・A surpasses a threshold and causes B・tense is dependent on the main clause・often used with words describing feelings]
Do people actually speak the way these example sentences are written? I feel like most of them should be using あまりに instead of just あまり...
Hey 
Actually, 「あまり」by itself is used more often, especially in speechm, than あまりに. I think it might be because it’s shorter.
Cheers! 
That’s so interesting. I’ll have to look out for it more when reading and watching anime.
Hey, I noticed a mistake on the notes of this grammar point:
The references cite to page 72 of A Dictionary of Basic Japanese Grammar, and while that page is indeed related to あまり, it’s targeted towards the use of “not much”, as in 「昨日、あまり寝られなかった」
I dug through my books and found out that the actual use seen here is on page 3 of A Dictionary of Intermediate Japanese Grammar. Could we update that accordingly?
Thanks in advance!
Fixed! 
Sorry for the inconvenience and thank you very much!
It’s no inconvenience! I work on app development too so I know how these things go, I’m just happy to help!
In this video they also use the construction:
あまりの(名詞)に
A general question about how the み suffix applies here. I’ve just looked it up, as I’d not come across it before, and wiktionary says that it expresses the quality of an adjective, where さ expresses the degree of said quality. Since the grammar point is specifically about such a degree as to cause a result, when would the み version be used? It doesn’t seem there are any examples of it to try to compare the two, either.
Thanks,
Cris
Hey @CrisH!
I’d like to first build upon what you’ve already said. Both ～み and ～さ nominalize adjectives. Note the following:
You really only would see this it if its an adjective that can only nominalize with み. You can confirm this by searching what would be the さ or み nominalizations and see if they come up in a dictionary. If they don’t, it’s safe to assume they can only be used with the one that did come up.
In the event of an adjective that can turn into both such as 悲しい, the meaning is almost interchangeable (so much of X that…) but, as the basic meaning of these nominalizations imply, み would focus on the quality itself while さ would focus on the amount of said quality, which is why this one is more used.
But at the end of the day I don’t think it’s a big change.
Hey, I have a question about one of the examples for this grammar point. This isn’t strictly related to the grammar in question but other part of the sentence:
旅行への楽しみさの余り、今日は寝れなさそう
What is the なさ in 寝れなさそう?
Still about the example sentence
旅行への楽しみさのあまり、今日は寝れなさそう。
I’m fine with either 楽しみ or 楽しさ and the difference was nicely explained by @Daru above. However, I am seriously confused that we have both み and さ at the same time. Is this really correct? It seems I can find this combination nowhere else and (if that counts for anything) it does not seem to make so much logical sense to nominalize first with み and then nominalize again with さ. It does make sense maybe to say you nominalize 楽しみ as a な-Adjective? Anyway I would just like to confirm that this isn’t a typo.
I came here because I stumbled upon the same issue. Could anyone explain this please?
This grammar point trips me up nearly every single time. I’m so used to using it in negative sentences that I am finding it hard to train my brain to recognize when to use it in a positive way
The explanation says:
［い］Adjective［み］+ の + あまり + (Negative Result) Phrase
The sentence is:
旅行が楽しみ____、今日は寝れなさそう。
“のあまり” fails hard and gets corrected to “なあまり”. Someone please explain 
Hey @Isurandil492 !
This gets corrected to なあまり since 楽しみ is a な-adjective! Since it is a な-adjective, it will follow the structure ‘［な］Adjective + な + あまり + (Negative Result) Phrase’
I hope this answers your question!
楽しみ is such a confusing word if you think about it too much. Dictionaries also list it as a noun in addition to な-adjective, and there are usages like 楽しみの一つ、楽しみのために、楽しみの方が that place it as a noun.
I think it has something to do with expectation of enjoyment vs just enjoyment in vacuum? But not sure.
I’m just glad this sentence no longer uses 「楽しみさ」
So, the issue is that it is not a form of 楽しい, but a word on its own. How would that sentence have to look if we were to use 楽しい?
