问题
Should I conceptualize a right fold as "folding the list to the right" or as "folding a list from the right"?
In other words, does a right fold go from left-to-right or from right-to-left?
回答1:
Right fold goes from right to left.
Left fold goes from the left, like you read a text - from left to right.
来源：https://stackoverflow.com/questions/28461908/how-should-i-conceptualize-a-right-fold-vs-a-left-fold