Fixity resolution: Infix operators are re-associated according to
圖像來源，US House Oversight Committee
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The first problem is wasted work again. If cell A1 references B8, and cell A2 also references B8, then when we update all the cells, we still only want to evaluate B8 once, and then reference it in both A1 and A2. We can do this through caching — whenever we calculate a cell’s value, we store it somewhere, and then all future cell references can used the stored value instead of recalculating.
id substr(key,1,40) created_at byte_size