This is a nice solution because it could apply more than just formulas - like integration with external data sources. With your spreadsheet being web-based, that might give it a killer purpose to be database-connected instead of just an simple excel clone. Anyways, you probably want to store the data so you'll have to send it over the wire at some point.
Yes, doing formulas (especially the simpler ones) client-side is important even if you send to the server, because nobody would want to wait for an ajax response to say sum(A1:A5) when its such an easy calculation, so it seems like the right approach to start there.
For some reason, I wasn't able to create a formula. I guess I'm doing something wrong with the syntax, or maybe I'm just assuming it would work like excel and something is off (as of course its still very new untested software so thats reasonable).
Anyways, recursive formulas are a trick. If you haven't figured it out, I would suggest making a stack of the recursive calls (such as A1=sum(B1) and B1=sum(A1)) then going over it until you see the same cell used within the nested expression.
With it, you can walk through the cells with the arrow-keys, select blocks of cells (like in your version), but also multiple blocks using CTRL.
For the formulas you need to create listeners, e.g. at the cells.
like if you use c3 = a1 + a2, each change of a1 or a2 need to change c3 as well. don't forget to remove listeners if you change / remove formulas.
Turkiyenin en sevilen filmlerinin yer aldigi xnxx internet sitemiz olan ve porn sex tarzi bir site olan mobil porno izle sitemiz gercekten dillere destan bir durumda herkesin sevdigi bir site olarak tarihe gececege benziyor. Sitenin en belirgin ozelliklerinden birisi de Turkiyede gercekten kaliteli ve muntazam, duzenli porno izle siteleri olmamasidir. Bu yuzden iste. Ayrica en net goruntu kalitesine sahip adresinde yayinlanmaktadir. Mesela diğer sitelerimizden bahsedecek olursak, en iyi hd porno video arşivine sahip bir siteyiz. "The Best anal porn videos and slut anus, big asses movies set..."