Peek First Element for One Key

Returns the first element whose key equals key.

Usage

peek_key(x, key)

Arguments

x

An ordered_sequence.

key

Query key.

Value

Matched element, or NULL when no matching key exists.

Details

For duplicate keys, this returns the first element in stable sequence order.

Examples

x <- ordered_sequence("a", "b", "c", keys = c(1, 2, 2))
peek_key(x, 2)
#> [1] "b"
peek_key(x, 10)
#> NULL