toString {base}

R Documentation

Convert an R Object to a Character String or Test for a String

Description

is.string(x) is checking if x is a “string”, i.e., a character vector of length(x) == 1.

toString() is a helper function for format to produce a single character string describing an R object.

Usage

is.string(x)

toString(x, ...)

## Default S3 method:
toString(x, width = NULL, collapse=", ", ...)

Arguments

x	the R object to be converted.
width	Suggestion for the maximum field width. Values of NULL or 0 indicate no maximum. The minimum value accepted is 6 and smaller values are taken as 6.
collapse	passed to paste(x, *) when concatenating elements.
...	optional arguments passed to or from methods.

Details

toString is a generic function for which methods can be written: only the default method is described here. Most methods should honor the width argument to specify the maximum display width (as measured by nchar(type = "width")) of the result.

The default method first converts x to character and then concatenates the elements separated by collapse, by default, ", ". If width is supplied and is not NULL, the default method returns the first width - 4 characters of the result with .... appended, if the full result would use more than width characters.

Value

is.string() returns TRUE or FALSE.

toString(.) returns a ‘string’, i.e., a character vector of length 1.

Author(s)

Robert Gentleman

See Also

format

Examples

x <- c("a", "b", "aaaaaaaaaaa")
toString(x)
toString(x, width = 8)

is.string(x)   # FALSE : a character vector of length 3
is.string(x[1]) # TRUE
is.string("")   # TRUE
is.string(NA_character_) # TRUE
is.string(character(0)) # FALSE
stopifnot(!is.string(x), !is.string(character()), is.string("abc"), is.string(x[1]))

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