mirror of
https://github.com/unisonweb/unison.git
synced 2024-08-15 13:30:27 +03:00
0031542faf
This is for consistency with the `cmark` style. Now the blocks we still pretty-print ourselves will match the bulk of them that `cmark` produces.
2.0 KiB
2.0 KiB
A simple transcript to test the use of exceptions that bubble to the top level.
FYI, here are the Exception and Failure types:
scratch/main> view Exception Failure
structural ability builtin.Exception where
raise : Failure ->{builtin.Exception} x
type builtin.io2.Failure
= Failure Type Text Any
Here's a sample program just to verify that the typechecker allows run to throw exceptions:
use builtin IO Exception Test.Result
main : '{IO, Exception} ()
main _ = ()
mytest : '{IO, Exception} [Test.Result]
mytest _ = [Ok "Great"]
Loading changes detected in scratch.u.
I found and typechecked these definitions in scratch.u. If you
do an `add` or `update`, here's how your codebase would
change:
⍟ These new definitions are ok to `add`:
main : '{IO, Exception} ()
mytest : '{IO, Exception} [Result]
scratch/main> run main
()
scratch/main> add
⍟ I've added these definitions:
main : '{IO, Exception} ()
mytest : '{IO, Exception} [Result]
scratch/main> io.test mytest
New test results:
1. mytest ◉ Great
✅ 1 test(s) passing
Tip: Use view 1 to view the source of a test.
Now a test to show the handling of uncaught exceptions:
main2 = '(error "oh noes!" ())
error : Text -> a ->{Exception} x
error msg a =
builtin.Exception.raise (Failure (typeLink RuntimeError) msg (Any a))
unique type RuntimeError =
Loading changes detected in scratch.u.
I found and typechecked these definitions in scratch.u. If you
do an `add` or `update`, here's how your codebase would
change:
⍟ These new definitions are ok to `add`:
type RuntimeError
error : Text -> a ->{Exception} x
main2 : '{Exception} r
scratch/main> run main2
💔💥
The program halted with an unhandled exception:
Failure (typeLink RuntimeError) "oh noes!" (Any ())
Stack trace:
##raise