toString

[evancz]

Easy Problems

• #472 - Adds parens around lists

Bad Input

• #654 - Record with ctor field.
• #645 - Json.Value with cyclical references
• #539 - Json.Value with cyclical references (no http://sscce.org)
• #812 - union types with particular names

The root problem here is that toString should return something like <js> when given a Json.Value of any kind. This can arise in a few situations.

Possible solution: reintroduce _ field to all records. This way it is clear when something is a union type or record or JSON value. You can still cheat, but it will be more rare. This has a cost in the size of all record allocations.

[evancz]

#472 about parens should be fixed by elm-lang@b6b85af

The ctor thing should be solved by switching to $ for that name.

The JSON ones should be solved by the _Json_wrap and _Json_unwrap pattern, allowing me to show <internals> for all of those values.

I don't know if there is a fix for #812 at this time, but I'll wait til someone reopens something on it.

[evancz]

#472 about parens should be fixed by elm-lang@b6b85af

The ctor thing should be solved by switching to $ for that name.

The JSON ones should be solved by the _Json_wrap and _Json_unwrap pattern, allowing me to show <internals> for all of those values.

I don't know if there is a fix for #812 at this time, but I'll wait til someone reopens something on it.