Issues using rejected & pending promises as values in viewof cells

[joshuahhh]

Describe the bug

Please see https://observablehq.com/d/137b4f7f2697819b for a walkthrough of the problem.

To summarize: If you set .value of a viewof cell to a rejected promise, or a hang-forever promise, and then you set it back to a normal value, the normal value is ignored and the error / pending status remains.

To Reproduce
Please see https://observablehq.com/d/137b4f7f2697819b for a reproduction.

Expected behavior
I would expect setting a new value for .value to override the old value. This would be in line with the way Observable's runtime works for derived values returning rejected or pending promises, as I show in the linked notebook.

Screenshots
N/A.

Desktop (please complete the following information):

• Mac 13.3
• Chrome 112

Additional context
Thanks a bunch!

[mootari]

Related:

• Recovering from promise rejection
• https://observablehq.com/@mootari/of-promises-and-heartbreaks
• Generators.observe needs a better way to throw? (And end?) stdlib#44