Chain JS calls in interop

1

Hello,
I know it is possible to chain props access in bucklescript, but I am not sure if it is possible to write bindings that call chained functions.
I know that you can define externals with bs.send and then they will be compiled to just chained calls, but If I want to build a helper function that is just several external calls chained it will be compiled to an actual function instead of a zero cost call.
To put an example, this is what I have:

external getDataRange : sheet -> range = "getDataRange"  [@@bs.send]    
external getValues : range -> Cell.t array array = "getValues"  [@@bs.send]
let getAllValues sheet =  getDataRange sheet |. getValues

But this is what I wanted:

external getDataRange : sheet -> range = "getDataRange"  [@@bs.send]    
external getValues : range -> Cell.t array array = "getValues"  [@@bs.send]
external getAllValues : sheet -> Cell.t array array = "getDataRange().getValues"  [@@bs.send]

But the above produces wrong JS code. If this even possible?

2

Not really possible.

3

IMO zero cost is best for the direct access it supports only. If this is something you’re likely to use often, a helper function is arguably better because it’ll result in less bundle size than if the chained calls were inlined all the time.

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