Dan Licata

Types and cats.

[Dan Licata @admitscut]

@TaliaRinger this dinosaur waffle maker is fun. Can reheat them in it for a few days in a row https://t.co/yuLhIIHOfR

[Dan Licata @admitscut]

@alpha_convert @joomy Congrats!

[Dan Licata @admitscut]

@joomy But the idea of “intrinsic verification” is certainly in the Epigram papers, the Power of Pi, etc. or anything that uses Vec A n as opposed to lists with predicates about the length. I don’t remember if those papers use that terminology though

[Dan Licata @admitscut]

@joomy you could have an “intrinsic semantics” in reynolds’ sense without using dependent types. The way we were using the terminology for twelf is the same as how I use it for agda

[Dan Licata @admitscut]

@joomy @Enetsee So the first meaning of "nested" is language (datatype mechanism) dependent.

[Dan Licata @admitscut]

@joomy @Enetsee Like if Haskell didn't allow data T where C : A -> B -> T then would a constructor C : (A,B) -> T count A and B as "immediate" positions? What about Pair A B -> T for a user-defined Pair type?

[Dan Licata @admitscut]

@joomy @Enetsee (E.g. in Coq/Agda it has to be strictly positive.)

[Dan Licata @admitscut]

@joomy @Enetsee I'd call the second one a nested type, and the first one "the grammar for inputs to datatype constructors includes the following type constructors:..."

[Dan Licata @admitscut]

@ionathanch Technically Pennsylvania is a commonwealth…

[Rose Bohrer @rose_bohrer]

RT appreciated:
I am happy to announce the official V1 of the Human-Centered Programming Languages textbook, the first book to fully blend PL foundations and human-centered computing with up-to-date research. Open access at: https://t.co/q5qimPR3U9
Paper: https://t.co/saNdJoPNtY

[Dan Licata @admitscut]

@MamaWeasleyy CDC director says it’s “perfectly ok”https://t.co/CpV7VuGvqf around minute 21

[Dan Licata @admitscut]

@MamaWeasleyy Some Walgreens around Hartford have pediatric moderna (pharmacist administering to 3 years old to 11 years old).

[Dan Licata @admitscut]

@MamaWeasleyy I’d like to know if anyone knows any <5 anywhere in CT (it looked like some Walmarts might have had moderna but it went fast).

[Dan Licata @admitscut]

@TaliaRinger I'm mostly kidding but
class List:
class Nil(List):
class Cons(List):
def __init__(self, x : int, xs : List)

[Dan Licata @admitscut]

@TaliaRinger "A list is either
- Nil, or
- Cons(x,xs), where x is an int and xs is a list" ?

[Stephanie Weirich @fancytypes]

The program for the Oregon PL Summer School 2023 is now available and the application deadline is April 13th! Apply here: https://t.co/iFvuEXuw1K

[Dan Licata @admitscut]

@jonmsterling Better than being confused about what city your wedding is in tho (congrats!).