extractClaimValue<R> function
Implementation
R extractClaimValue<R>(Claim claim, String claimName) {
final extendedClaim = decodeBase64URL(claim.value, claim.indexMod4);
final (name, value) = verifyExtendedClaim(extendedClaim);
if (name != claimName) {
throw ArgumentError("Invalid field name: found $name expected $claimName");
}
return value;
}