Check if an argument is a valid CUSIP string

Validates CUSIP format including Luhn-variant check digit verification.

Usage

is_cusip(x)

Arguments

x

(any)
Object to check.

Value

TRUE if x is a valid CUSIP string, FALSE otherwise.

References

https://en.wikipedia.org/wiki/CUSIP

Examples

is_cusip("037833100")
#> [1] TRUE