dreamerr: Error Handling Made Easy

plural

R Documentation

Adds an s and/or a singular/plural verb depending on the argument's length

Description

Utilities to write user-level messages. These functions add an ‘s’ or a verb at the appropriate form depending on whether the argument is equal to unity (plural) or of length one (plural_len).

Usage

plural(x, type, s, verb = FALSE, past = FALSE)

plural_len(x, type, s, verb = FALSE, past = FALSE)

Arguments

`x`	An integer of length one (`plural`) or a vector `plural_len`.
`type`	Character string, default is missing. If `type = "s.is.past"` it means that an "s" will be added if `x` is greater than 1 (or of length greater than one for `plural_len`); it will be followed by the verb "to be" in past tense in singular or plural form depending on `x`. This argument must be made of keywords separated by points without space, the keywords are "s", "past" and a verb (i.e. any thing different than "s" and "past"). Missing keywords mean their value is equal to `FALSE`.
`s`	Logical, used only if the argument type is missing. Whether to add an "s" if the form of `x` is plural. Default is missing: equals to `TRUE` if no other argument is provided, `FALSE` otherwise.
`verb`	Character string or `FALSE`, used only if the argument type is missing. The verb to be inserted in singular or plural depending on the value of `x`. default is `FALSE`.
`past`	Logical, used only if the argument type is missing. Whether the verb should be in past tense. Default is `FALSE`.

Value

Returns a character string of length one.

Functions

plural_len(): Adds an s and conjugate a verb depending on the length of x

Author(s)

Laurent Berge

Examples


# Let's create an error message when NAs are present
my_crossprod = function(mat){
 if(anyNA(mat)){
   row_na = which(rowSums(is.na(mat)) > 0)
   n_na = length(row_na)
   stop("In argument 'mat': ", n_letter(n_na), " row", plural(n_na, "s.contain"),
        " NA values (", ifelse(n_na<=3, "", "e.g. "), "row",
        enumerate_items(head(row_na, 3), "s"),
        "). Please remove ", ifunit(n_na, "it", "them"), " first.")
 }
 crossprod(mat)
}

mat = matrix(rnorm(30), 10, 3)
mat4 = mat1 = mat
mat4[c(1, 7, 13, 28)] = NA
mat1[7] = NA

# Error raised because of NA: informative (and nice) messages
try(my_crossprod(mat4))
try(my_crossprod(mat1))

lrberge/dreamerr documentation built on Oct. 12, 2024, 5:49 a.m.