Using the bracket notation ("[") as a function in R

usingSelectionAsAFunction.R

x = list("red",
         "green",
         "blue")
print(x)
# [[1]]
# [1] "red"
# 
# [[2]]
# [1] "green"
# 
# [[3]]
# [1] "blue"

sapply(X = x,
       FUN = "[")
# [1] "red"   "green" "blue" 

myData = data.frame(cholesterol = 240)
typeof(y)
# "list"

typeof(
  sapply(
    X = myData,
    FUN = "["
  )
)
# "double"