This library never throws exceptions to signal error. In general, the library returns a StatusOr if an error is possible. Some functions return objects that are not wrapped in a StatusOr<T> but will themselves return a StatusOr<T> to signal an error. For example, wrappers for asynchronous operations return future<StatusOr<T>>.
Applications should check if the StatusOr<T> contains a value before using it, much like how you might check that a pointer is not null before dereferencing it. Indeed, a StatusOr<T> object can be used like a smart-pointer to T, with the main difference being that when it does not hold a T it will instead hold a Status object with extra information about the error.
You can check that a StatusOr<T> contains a value by calling the .ok() method, or by using operator bool() (like with other smart pointers). If there is no value, you can access the contained Status object using the .status() member. If there is a value, you may access it by dereferencing with operator*() or operator->(). As with all smart pointers, callers must first check that the StatusOr<T> contains a value before dereferencing and accessing the contained value. Alternatively, callers may instead use the .value() member function which is defined to throw a RuntimeStatusError if there is no value.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-07-09 UTC."],[[["This page documents error handling in the Bigtable C++ library, focusing on how errors are managed without the use of exceptions."],["The library uses `StatusOr\u003cT\u003e` to indicate potential errors, similar to a smart pointer, and applications must check if it contains a value before accessing it."],["You can determine whether `StatusOr\u003cT\u003e` contains a value using the `.ok()` method or `operator bool()`, and retrieve the `Status` object via `.status()` if no value is present."],["Access the contained value in `StatusOr\u003cT\u003e` by dereferencing with `operator*()` or `operator-\u003e()`, or by using `.value()`, which throws `RuntimeStatusError` if there's no value (or terminates if exceptions are disabled)."],["The page includes a example of how to use `StatusOr\u003cT\u003e` in a read row operation, and contains references to the documentation of `google::cloud::StatusOr`, `google::cloud::Status` and `google::cloud::future`."]]],[]]
