# Does replyr::let work with data.table?

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I’ve been asked if the adapter “`let`

” from our `R`

package `replyr`

works with `data.table`

.

My answer is: it does work. I am not a `data.table`

user so I am not the one to ask if `data.table`

benefits a from a non-standard evaluation to standard evaluation adapter such as `replyr::let`

.

Using `replyr::let`

with `data.table`

looks like the following:

library("data.table") library("replyr") data("iris", package= "datasets") iris.dt <- data.table(iris) # non-standard evaluation, column names hard-coded iris.dt[, mean(Sepal.Length), by=Species] # standard evaluation, column names parameterized let( list(GROUPCOL='Species', DATACOL='Sepal.Length'), iris.dt[, mean(DATACOL), by=GROUPCOL] )

I’ve generated some timings to show there is some overhead in the translation (especially on trivial examples):

If any `data.table`

users want to comment if this is useful or not, I’d be happy to hear from you.

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