# function reporting the sum of a variable
sum_var = function(data, var){
# var: a variable name, should be part of data
if(!var %in% names(data)){
suggestion = suggest_item(var, names(data), msg.write = TRUE)
stopi("The variable `{var}` is not in the data set. {suggestion}")
}
sum(data[[var]])
}
# The error message guides us to a suggestion
try(sum_var(iris, "Petal.Le"))
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