r - how to use select for multiple fields using dplyr -

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i have character vector of field names want select using dplyr. i'm using underscore version of select_().

select(mtcars, mpg)                   # works ok select(mtcars, mpg, disp, am)         # works ok multiple fields

now let's use underscore version

fie <- c("mpg")              select_(mtcars, fie)                  # works ok 1 fie <- c("mpg", "disp", "am") select_(mtcars, fie)                  # problem:  returns 1 column select_(mtcars, ~fie)                 # problem:  doesn't work

i'm confused how work. suggestions?

if use select:

select(mtcars, one_of(fie))

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