Project Fortress

  • 3,765 views
Uploaded on

An overview of Project Fortress, a research language being developed at Sun, focusing on scientific and large-scale computing.

An overview of Project Fortress, a research language being developed at Sun, focusing on scientific and large-scale computing.

More in: Technology , Education
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
  • Late-breaking note - on slide 10 - the type is not optional on mutable variables as it is unknown at declaration time what future values might be assigned
    Are you sure you want to
    Your message goes here
No Downloads

Views

Total Views
3,765
On Slideshare
0
From Embeds
0
Number of Embeds
2

Actions

Shares
Downloads
43
Comments
1
Likes
4

Embeds 0

No embeds

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide

Transcript

  • 1. Project Fortress Alex Miller http://www.flickr.com/photos/micbaun/1216608114/ Wednesday, July 1, 2009
  • 2. Dude, isn’t Fortress like FORTRAN or something? http://www.flickr.com/photos/finkle/3111290180/ Wednesday, July 1, 2009
  • 3. Um, no. Wednesday, July 1, 2009
  • 4. Modern language design + Scientific computing Wednesday, July 1, 2009
  • 5. Features of interest Mathematical rendering Parallelism Software transactional memory Operator and function overloading Objects / traits Contracts Components / apis Wednesday, July 1, 2009
  • 6. Let’s build some basics Wednesday, July 1, 2009
  • 7. Types ZZ32, ZZ64 - signed integer types RR32, RR64 - floating point types String Boolean Wednesday, July 1, 2009
  • 8. juxtaposition 3 4 evaluates to 12 “a” “b” evaluates to “ab” log 1 evaluates to 0 Wednesday, July 1, 2009
  • 9. Ranges 5:9 evaluates to [5,6,7,8,9] 5:9:2 evaluates to [5,7,9] 5#2 evaluates to [5,6] Wednesday, July 1, 2009
  • 10. Variables Immutable: name[:type] = value zero = 0 zero:ZZ32 = 0 Mutable: var name[:type] = value OR name[:type] := value var sum = 0 sum := 0 Wednesday, July 1, 2009
  • 11. Now you’re dangerous. Wednesday, July 1, 2009
  • 12. A simple example component fact export Executable fact(n:ZZ32): ZZ32 = if n = 0 then 1 else n fact(n-1) end run():()=do for k<-seq(1:10) do println " fact(" k ") = " fact(k) end end end Executable - a trait juxtaposition as operator defining run() Parallelism - in terms, in for Rendering: ZZ32, <-, fonts seq() - force sequential Wednesday, July 1, 2009
  • 13. BIG ideas But factorial is just a big multiply...use aggregate PROD operator ∏ instead. This is known as a BIG operator. Wednesday, July 1, 2009
  • 14. More direct implementation component factp export Executable factp(n:ZZ32): ZZ32 = PROD [i <- 1:n] i run():()=do for k<-seq(1:10) do println " factp(" k ") = " factp(k) end end end PROD = aggregate Known as “BIG” product operators SUM = summation You can make your own! Wednesday, July 1, 2009
  • 15. Operator overloading Would be nice to actually use the right mathematical operator ! instead of a function, wouldn’t it? Wednesday, July 1, 2009
  • 16. Let’s make it an operator component facto export Executable opr(n:ZZ32)! = PROD [i <- 1:n] i run():()=do for k<-seq(1:10) do println k "! = " k! end end end opr() used to define a Also can do prefix, infix, postfix operator here nofix, multifix, or enclosing! Wednesday, July 1, 2009
  • 17. Lists evens = <|[ZZ32] 2,4,6,8,10|> println "evens: " evens evens2 = <|[ZZ32] 2 x | x <- 1:5|> println "evens2: " evens2 odds = <|[ZZ32] e - 1 | e <- evens |> println "odds: " odds evens: <|2, 4, 6, 8, 10|> evens2: <|2, 4, 6, 8, 10|> odds: <|1, 3, 5, 7, 9|> Wednesday, July 1, 2009
  • 18. Another example component sos import List.{...} export Executable sumOfSquares(n:List[ZZ32]): ZZ64 = do sum:ZZ64 := 0 for i<-0#|n| do sum += (n[i])^2 end sum end run():()=do theList = <|[ZZ32] x | x<-1#100|> println "sumOfSquares = " sumOfSquares(theList) end end What’s the bug? (Hint: think parallelism) Wednesday, July 1, 2009
  • 19. Implicit parallelism Many things implicitly parallel for loops parameters to a function call do ... also ... end construct Here, for loop is parallel, so sum += is a data race Use atomic to fix Wednesday, July 1, 2009
  • 20. Atomic punk component sos import List.{...} Fortress uses Software export Executable Transactional Memory sumOfSquares(n:List[ZZ32]): ZZ64 = do atomic blocks executed all sum:ZZ64 := 0 for i<-0#|n| do or nothing atomic sum += (n[i])^2 end sum Retry on collision end run():()=do theList = <|[ZZ32] x | x<-1#100|> println "sumOfSquares = " Transactions may nest sumOfSquares(theList) end tryatomic end Wednesday, July 1, 2009
  • 21. Traits component traitexample export Executable trait - like Java interface trait Animal talk():String end methods - abstract or trait Fuzzy concrete howFuzzy():String end object - like Java final class trait Cat extends Animal fields, methods getter name():String talk() = "meow" end object Whiskers extends {Cat, Fuzzy} constructors name() = "Whiskers" howFuzzy() = "real fuzzy" end multiple inheritance run():() = do w:Whiskers = Whiskers getter / setter - metadata println w.name() " is " w.howFuzzy() end end Wednesday, July 1, 2009
  • 22. Function contracts component factc export Executable Documentation of factorial(n:ZZ32):ZZ32 semantic constraints requires { n >= 0 } ensures { outcome >= 0 } beyond the type system. = PROD [i <- 1:n] i run():() = do requires - specifies pre- conditions on incoming for k<-seq(1:10) do println k "! = " factorial(k) arguments end end end ensures - specifies post- condition on “outcome” Wednesday, July 1, 2009
  • 23. Components and APIs Components modularize your program Components export and import APIs (NEVER other components, just APIs) APIs are explicitly defined in their own file type Repository for components Wednesday, July 1, 2009
  • 24. And more... Literal arrays, multi-dimensional arrays Maps, sets, skip lists, trees, heaps, sparse vectors and matrices, quick sort, etc in library Explicit thread spawn, memory region tree Function overloading Tuples Tests Functions as first class objects Exceptions Wednesday, July 1, 2009
  • 25. Whither next? Currently working on compiler Goal is to have it working in 6 months for a real bioinformatics project Wednesday, July 1, 2009
  • 26. For more... Project Home: http://projectfortress.sun.com/Projects/ Community David Chase: http://www.infoq.com/presentations/ chase-fortress Guy Steele, Eric Allen: http://tinyurl.com/md6f6g Wednesday, July 1, 2009
  • 27. Alex Miller Twitter: http://twitter.com/puredanger Blog: http://tech.puredanger.com Presentations: http://slideshare.net/alexmiller Wednesday, July 1, 2009