/// 'requireState(X)' is used to indicate callee-state-related preconditions that callers must satisfy.
/// Failure to satisfy indicates a stateful bug in either the caller or the callee.
#define requireState(expr) if (!(expr)) [BadState raise:[NSString stringWithFormat:@"required state: %@ (in %s at line %d)", (@#expr), __FILE__, __LINE__]]
/// 'checkOperation(X)' is used to throw exceptions if operations fail.
/// Failure does not indicate a bug.
/// Methods may throw these exceptions for callers to catch as a 'returned error' result.
/// 'checkOperationDescribe(X, Desc)' is used to throw exceptions if operations fail, and describe the problem.
/// Failure does not indicate a bug.
/// Methods may throw these exceptions for callers to catch as a 'returned error' result.
#define checkOperationDescribe(expr, desc) if (!(expr)) [OperationFailed raise:[NSString stringWithFormat:@"Operation failed: %@ Expected: %@(in %s at line %d)", (desc), (@#expr),__FILE__,__LINE__]]
/// 'checkSecurityOperation(X, Desc)' is used to throw exceptions if operations fail due to authentication or other crypto failures, and describe the problem.
/// Failure does not indicate a bug.
/// Methods may throw these exceptions for callers to catch as a 'returned error' result.
#define checkSecurityOperation(expr, desc) if (!(expr)) [SecurityFailure raise:[NSString stringWithFormat:@"Security related failure: %@ Expected: %@(in %s at line %d)", (desc), (@#expr),__FILE__,__LINE__]]