magrittr operator %>% is evaluated before modules $ operator

[mschubert]

MWE from ebits, both b$min and sum have one required and one named default argument.

The first example that throws an error here should work. This might be an R bug though.

library(modules)
b = import('base')
c(1:100) %>% b$minN
# Error in `c(1:100)`$b : 3 arguments passed to '$' which requires 2
c(1:100) %>% (b$minN)
# [1] 2
c(1:100) %>% b$minN(N=2)
# [1] 2
c(1:100) %>% sum
# [1] 5050
c(1:100) %>% sum(na.rm=T)
# [1] 5050

[klmr]

This is a “bug” in magrittr, not modules. However, they would probably argue that it’s by design¹. The “correct” way to make this work is:

c(1:100) %>% b$minN()

However, I think it might be worth reporting this anyway, and see whether the magrittr folks agree.

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¹ It’s required to make the syntax foo %>% .$something work.

[mschubert]

Yes, you are right.

I could also reproduce the example by putting a function in a list, without modules involvement.