Safe Haskell | Safe |
---|---|
Language | Haskell2010 |
Synopsis
- data ISBN = ISBN10 Text
- validateISBN10 :: Text -> Either ISBN10ValidationError ISBN
- data ISBN10ValidationError
- renderISBN10ValidationError :: ISBN10ValidationError -> Text
- confirmISBN10CheckDigit :: Text -> Bool
- calculateISBN10CheckDigitValue :: Text -> Int
- isbn10CharToNumericValue :: Char -> Int
- numericValueToISBN10Char :: Int -> Char
- isValidISBN10CheckDigit :: Char -> Bool
- isNumericCharacter :: Char -> Bool
- unsafeToISBN10 :: Text -> ISBN
Documentation
Data type for representing ISBN values. Values of this type should be
created safely using validateISBN
, which will produce ISBN10
or ISBN13
values after validating the input.
The validateISBN10
and validateISBN13
functions can
also be used to only attempt to create ISBNs of a specific type.
When importing this data type, it is recommended not expose the
constructors, and instead use unsafeToISBN10
or
unsafeToISBN13
to coerce Text
values into ISBN
values.
validateISBN10 :: Text -> Either ISBN10ValidationError ISBN Source #
Used to safely create ISBN10
values represented by the ISBN
data type.
Assumes that the Text
input is an ISBN-10 string, either with or
without hyphens.
Will return either a validated ISBN-10 or an ISBN10ValidationError
, which can be
rendered as a descriptive string using renderISBN10ValidationError
.
Examples:
validateISBN10 "0-345-81602-1" == Right (ISBN10 "0345816021") validateISBN10 "0345816021" == Right (ISBN10 "0345816021") validateISBN10 "0-807-01429-X" == Right (ISBN10 "080701429X") validateISBN10 "0-345-816" == Left ISBN10InvalidInputLength validateISBN10 "X-345-81602-1" == Left ISBN10IllegalCharactersInBody validateISBN10 "0-345-81602-B" == Left ISBN10IllegalCharacterAsCheckDigit validateISBN10 "0-345-81602-3" == Left ISBN10InvalidCheckDigit
Validation Errors
data ISBN10ValidationError Source #
Possible validation errors resulting from ISBN-10 validation.
ISBN10InvalidInputLength | The length of the input string is not 10 characters, not counting hyphens |
ISBN10IllegalCharactersInBody | The first nine characters of the ISBN-10 input contain non-numeric characters |
ISBN10IllegalCharacterAsCheckDigit | The check digit of the ISBN-10 is not a valid character ( |
ISBN10InvalidCheckDigit | The check digit is not valid for the given ISBN-10 |
Instances
Eq ISBN10ValidationError Source # | |
Defined in Data.ISBN.ISBN10 (==) :: ISBN10ValidationError -> ISBN10ValidationError -> Bool # (/=) :: ISBN10ValidationError -> ISBN10ValidationError -> Bool # | |
Show ISBN10ValidationError Source # | |
Defined in Data.ISBN.ISBN10 showsPrec :: Int -> ISBN10ValidationError -> ShowS # show :: ISBN10ValidationError -> String # showList :: [ISBN10ValidationError] -> ShowS # |
renderISBN10ValidationError :: ISBN10ValidationError -> Text Source #
Convert an ISBN10ValidationError
into a human-friendly error message.
Helpers
confirmISBN10CheckDigit :: Text -> Bool Source #
Confirms that the check digit of an ISBN-10 is correct. Assumes that the
input consists of 9 numeric characters followed by a legal check digit
character (0-9
or X
).
Examples:
confirmISBN10CheckDigit "0345816021" == True confirmISBN10CheckDigit "080701429X" == True
calculateISBN10CheckDigitValue :: Text -> Int Source #
Calculates an ISBN-10 check digit value using the standard check digit calculation formula. Assumes that the input is 9 numeric characters. The check digit value value can be any number in the range 0 to 10, the last of which is represented by the symbol 'X' in an ISBN-10.
See: https://en.wikipedia.org/wiki/International_Standard_Book_Number#ISBN-10_check_digits
Examples:
calculateISBN10CheckDigitValue "034581602" == 1 calculateISBN10CheckDigitValue "080701429" == 10
isbn10CharToNumericValue :: Char -> Int Source #
Converts an ISBN-10 character to a numeric value. Valid input characters
include 0-9
as well as X
.
numericValueToISBN10Char :: Int -> Char Source #
Converts a numeric value to an ISBN-10 character. Valid input values are the numbers from 0 to 10.
isValidISBN10CheckDigit :: Char -> Bool Source #
Validates a character as a valid ISBN-10 check digit character. ISBN-10
check digit characters include 0-9
as well as the symbol
. The lowercase
letter 'x' is not considered valid.X
isNumericCharacter :: Char -> Bool Source #
Determines whether a character is numeric (e.g. in the range of 0-9
).