rlang (version 0.2.1)

prepend: Prepend a vector

Description

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.

Usage

prepend(x, values, before = 1)

Arguments

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.

Value

A merged vector.

Life cycle

prepend() is experimental, expect API changes. We are still figuring out what vector tools belong in rlang.

Examples

# NOT RUN {
x <- as.list(1:3)

append(x, "a")
prepend(x, "a")
prepend(x, list("a", "b"), before = 3)
# }