R get max, keyed by another function (like in Python) -

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in python, can 

max(stuff, key=lambda x: abs(x.foo))

which return element of stuff has member foo highest absolute value.

how in r?

so suppose stuff must list of vectors (or lists) named elements, this:

stuff <- list( first = c(bang=1, qux = 2, foo = 3),                second = c(bang=6, qux = 0, foo= 100),                third = c(bang = 1, qux = 7, foo = 0))

you can element "foo" using sapply:

sapply(stuff, function(.) .['foo'])

... find maximum of it:

which.max(sapply(stuff, function(.) .['foo']))

... , use index list:

stuff[which.max(sapply(stuff, function(.) .['foo']))]

or magrittr:

stuff %>% {.[sapply(., "[", "foo") %>% which.max]}

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