is_valid_lc_call: Check if LC Call Number is valid
Description
Takes a string representation of a Library of Congress
call number and returns either TRUE or FALSE based on
whether or not the input fits the canonical LC Call
Number pattern
Usage
is_valid_lc_call(x, allow.bare = FALSE)
Value
Returns either TRUE or FALSE based on whether the
call number is valid
Arguments
x
A Library of Congress call number (string)
allow.bare
A logical indicating whether an LC Call with only
the letters should be considered valid
(default is FALSE)