Ok, let restart this conversation, actually there are two issues.

1/ there is no syntax for saying that a type is total or not,
   if we take a close look to the different mails, at some points several of us 
uses different syntax to show that part of a pattern is total,
   Guy has used '_', i've proposed 'default', Brian used a blank line after the 
pattern and we all have used "var" a some points.


2/ using an explicit type for a total type is a footgun because the semantics 
will change if the hierarchy or the return type of a method switched upon 
change.
   Getting an error by the compiler when the behaviour change is important.
   And devs are used to change something in their code and fix all the errors 
reported by the compiler (using the refactoring capability of the IDE or not),
   if we let people to use an explicit type as a total pattern, the change of 
semantics will go undetected.


We have currently discussed about 1/ and 2/ at the same time, but conflating 
the two is maybe a mistake.

I believe that before talking about 1/, we should determine if we should tackle 
2/ or not.

As i already said, for me 2/ is the real issue and i think Tagir agree.

Rémi

Reply via email to