Existence aware pick operator

Existence aware pick operator

Usage

env %.% field

Arguments

env

(object)
The object or environment to attempt to pick from

field

(character)
The name of the field to pick from env

Value

Error if the field does not exist in env, otherwise it returns field

Examples

 t <- list(a = 1, b = 2)

 t$a       # 1
#> [1] 1
 t %.% a   # 1
#> [1] 1

 t$c # NULL
#> NULL
 if (FALSE) {
 t %.% c # ERROR a not found in t
 }