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Version: v13.0.0

base64_url/2

Description​

base64_url/2 is a predicate that unifies a string to a Base64 URL-safe encoded string.

Encoded values are safe for use in URLs and filenames: "+" is replaced by "-", "/" by "_", and padding is omitted.

The signature is as follows:

base64url(+Plain, -Encoded) is det
base64url(-Plain, +Encoded) is det

Where:

  • Plain is an atom, a list of characters, or character codes representing the unencoded text.
  • Encoded is an atom, a list of characters, or character codes representing the Base64 URL-safe encoded form.

The predicate is equivalent to base64_encoded/3 with options: [as(atom), encoding(utf8), charset(url), padding(false)].