Rename "task failure" to "task panic", and
The current terminology of "task failure" often causes problems when
writing or speaking about code. You often want to talk about the
possibility of an operation that returns a
Result "failing", but
cannot because of the ambiguity with task failure. Instead, you have
to speak of "the failing case" or "when the operation does not
succeed" or other circumlocutions.
Likewise, we use a "Failure" header in rustdoc to describe when operations may fail the task, but it would often be helpful to separate out a section describing the "Err-producing" case.
We have been steadily moving away from task failure and toward
Result as an error-handling mechanism, so we should optimize our
Result-producing functions should be easy
Not much more to say here than is in the summary: rename "task
failure" to "task panic" in documentation, and
With this choice, we can use "failure" to refer to an operation that
None, "panic" for unwinding at the task level, and
"abort" for aborting the entire process.
The connotations of panic seem fairly accurate: the process is not immediately ending, but it is rapidly fleeing from some problematic circumstance (by killing off tasks) until a recovery point.
The term "panic" is a bit informal, which some consider a drawback.
Making this change is likely to be a lot of work.
Other choices include:
unwind!. These options reasonably describe the current behavior of task failure, but "throw" suggests general exception handling, and both place the emphasis on the mechanism rather than the policy. We also are considering eventually adding a flag that allows
fail!to abort the process, which would make these terms misleading.
abort!. Ambiguous with process abort.
die!. A reasonable choice, but it's not immediately obvious what is being killed.