[plt-dev] coding ideas from JaneStreet

From: Paulo J. Matos (pocmatos at gmail.com)
Date: Tue Apr 13 04:42:14 EDT 2010

Eli Barzilay <eli at barzilay.org> writes:

>> The code that I'm talking about is a dialect of typed scheme that has
>> ML-like type definitions and matching, with the same kind of errors
>> when matches don't cover all cases, and when there are patterns that
>> are not reachable.  It's working only for these type definitions (not
>> on the usual scheme types, not on unions, etc -- only on types that
>> were defined using the ML-ish form).  But for the class it provides
>> the same advantage that ML has -- if you extend the AST definition
>> with a new variant, the compiler will tell you where you're missing
>> cases to deal with it.
> (Oh, and while this is a dialect of TS, the code predates it, and did
> the same with plain scheme structs previously.)

Awesome, this one of my favourite features missing in Scheme. Hopefully
we will see this soon in TS, Sam?


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