prepend {rlang} | R Documentation |
This is a companion to base::append()
to help merging two lists
or atomic vectors. prepend()
is a clearer semantic signal than
c()
that a vector is to be merged at the beginning of another,
especially in a pipe chain.
prepend(x, values, before = 1)
x |
the vector to be modified. |
values |
to be included in the modified vector. |
before |
a subscript, before which the values are to be appended. |
A merged vector.
prepend()
is experimental, expect API changes. We are still
figuring out what vector tools belong in rlang.
x <- as.list(1:3) append(x, "a") prepend(x, "a") prepend(x, list("a", "b"), before = 3)