Does transduce take its arguments in the wrong order?

I realized something yesterday about transduce that has bothered me for a long time. Every time I use it I pretty much make a custom transducer function but the accumulator function and the initial argument pretty much only varies in two ways.

• Case 1: I build up a list of elements where xf is flip(append) and acc is []
• Case 2: I build up a sum where xf is add and acc is 0

Because of this, it seems a better argument order would be transduce(xf, acc, transducer, list). With this I could create

• transduceToList = transduce(flip(append), [])
• transduceToSum = transduce(add, 0)

I suspect that other uses of transduce would follow the same pattern.

I realize that transduce is not a ramda invention and that it probably follows a format from somewhere else. I just wanted to bring this up for discussion.

[CrossEye]

Yes, this is the expected behavior. There are several good articles, mostly Clojure related:

• http://gmorpheme.net/why-transducers-compose-backwards.html
• http://isaaccambron.com/blog/2014/12/13/transducer-composition.html

[franciscotln]

I’m having problem in understanding something kinda related to “order”. I’m using R.into with a composed transducer but the order of the functions calls inside R.compose is the opposite (left to right), like pipe, and vice-versa: using R.pipe the functions are called from right to left. https://goo.gl/ZuKUvN

Is this the expected behaviour?