Lambda the Ultimate

type	title	author	last post
Story	The Next Stage of Staging Parameterized types require special scoping rules by Hewitt	naasking	2015-04-07 14:58
Forum topic	Detected contradictions in large information systems Contradictions do not mean "annihilation." by Hewitt A contradiction is P and ¬P; even if said by different speakers by Hewitt "Correctness" vs. Ignore, Defer, Circumvent, & Ameliorate by Hewitt	Hewitt	2014-04-22 11:45
Forum topic	Modelling Actors with Locks Clarifying issues is not easy on LtU by Hewitt "Eventual consistency" is reconciliation and not consistency by Hewitt Adding excuses does not magically erase contradictions by Hewitt No mythical "eventual" consistency because no consistency by Hewitt Exactly when is eventual consistency realized? by Hewitt Banking industry does realize eventual consistency by Hewitt Application programs: Don't use locks, threads, channels, etc. by Hewitt Synchronously transferring between different banks: oxymoron by Hewitt	laforge49	2014-04-14 06:21
Forum topic	Avoiding Actor Deadlocks--JActor Efficiency of message passing is crucial by Hewitt Messages are immutable, Request Actors are not immutable by Hewitt Deadlocks can be detected and broken but not prevented by Hewitt Global virtual time does not apply to fully distributed systems by Hewitt Preserving message order imposes significant overhead by Hewitt An Actor can process messages in any order it chooses by Hewitt Not possible to avoid deadlock in fully-distributed systems by Hewitt Request Actors for messages (e.g. JActor) is inefficient :-( by Hewitt Messages are received in the order that they are received :-) by Hewitt Messages in transit are immutable because they must be by Hewitt	laforge49	2014-03-27 04:37
Story	Propositions as Types Modern Logic Programs: proofs using Jaśkowski natural deduction by Hewitt Modern Logic Programs superior to Curry-Howard correspondence by Hewitt The lambda calculus is inadequate for computation by Hewitt Jaśkowski's natural deduction is superior to Gentzen's for CS by Hewitt Proposition *is* a type by Hewitt	Manuel J. Simoni	2014-03-19 07:14
Forum topic	The Evolution of CS Papers Dijkstra had a problem with assignment, but didn't know it :-( by Hewitt Sorry that you didn't understand. by Hewitt Hoare gave up on Dijkstra's model of states with assignments by Hewitt It's not the goto; but the assignment command that is at fault by Hewitt	Sean McDirmid	2014-03-11 14:09
Story	Determinism Is Not Enough: Making Parallel Programs Reliable with Stable Multithreading Computation these days means concurrent computation by Hewitt Nondeterministic state machines cannot implement concurrency by Hewitt How can (concurrent) computation be rigorously defined? by Hewitt Erlang/OTP is inadequate with respect to hardware failures by Hewitt Which of the principles of Actors are satisfied by Erlang/OTP? by Hewitt Unfortunately, Erlang/OTP does not properly support Actors by Hewitt Defensive code for pervasive indeterminacy and inconsistency by Hewitt	Allan McInnes	2014-03-05 19:33
Forum topic	Inconsistency Robustness in Foundations Unclear by Hewitt Eval messages with types by Hewitt A programming language without types is hopeless in practice by Hewitt Implementing Eval messages requires type Any by Hewitt Syntactic stratification is unworkable for Computer Science by Hewitt Wittgenstein: self-referential propositions infer inconsistency by Hewitt Logical foundations are for axioms and Logic Programs by Hewitt	Hewitt	2014-02-26 20:00
Forum topic	Not that one, the other one! Existentially closed minds by Hewitt Compactness in logic is undesireable in Computer Science by Hewitt Arbiters cause indeterminacy in computation by Hewitt Hartmaninis & Stearns theory is *not* about concurrency by Hewitt Nondeterministic state machines cannot implement concurrency by Hewitt	Hank Thediek	2014-02-23 22:08
Forum topic	Parallelism and Concurrency in the Actor Model Quantum physics: relevant to theory and practice of computation by Hewitt Interaction creates reality locally by Hewitt Indeterminacy in Actors is local in accord with standard QM by Hewitt Accidental duplicate post by Hewitt Indeterminacy is fundamental to concurrency by Hewitt Organizations scale, but the limits are unknown by Hewitt Actor Model provides a foundation for Concurrent Computation by Hewitt The science of concurrent computaton is in its infancy by Hewitt Organizational compostion is *not* a "meaningless buzz phrase" by Hewitt Indeterminacy: *necessary* not omnipresent in concurrent systems by Hewitt ...	Hewitt	2014-02-21 05:06
Forum topic	Limitations of Prolog-style clausal programs Parallelism and Concurrency in the Actor Model by Hewitt Meaningful information can be more than assertions by Hewitt Meaningful information is not necessarily knowledge by Hewitt Meaningful information is *not* bits; although bits can be used by Hewitt Meaningful information is *not* in general reducible to bits. by Hewitt Meaningful information can have contradictions by Hewitt Denial is not viable in face of existent pervasive inconsistency by Hewitt "Snowden might be a whistleblower." is too wishy-washy by Hewitt Information Inconsistency: both intension and extension by Hewitt A propostion and its negation are contradictory by Hewitt ...	Hewitt	2014-02-11 10:53
Forum topic	A glimpse into a new general purpose programming language under development at Microsoft Void should be first-class and every type should be Nullable by Hewitt	Charles Torre	2014-01-27 05:08
Forum topic	Less is more. Axioms together with rules of inference are insufficient by Hewitt	Rys McCusker	2014-01-19 13:05
Forum topic	Different approaches to letting a programmer define interface implementations. An Interface should allow any conforming implementation by Hewitt	Kannan Goundan	2014-01-15 04:00
Story	Pure Subtype Systems "Type" is both of type "Type" and a subtype of "Type" by Hewitt Notation for programming languages with first-class types by Hewitt ":=" is not good for the subtype relationship; use "≺:"? by Hewitt An Actor type needs to respond to an Extends[aType] message by Hewitt Types as first-class Actors by Hewitt Need types for both variable assignment and identifier binding by Hewitt	naasking	2014-01-14 06:09
Forum topic	Inconsistency Robustness in Logic Programs Logic Programs should be monotonic for assertions and goals by Hewitt Negation as Failure: less proveable means more can be asserted! by Hewitt Negation as failure (from Planner): ||- (¬⊢p) → ⊢¬p by Hewitt Prolog doesn't even have mechanism for concurrent inference by Hewitt Prolog does not concurrently backward and forward chain :-( by Hewitt Future of Logic Programs is many-core concurrency by Hewitt Prolog developed as a backward chaining subset of Micro-Planner by Hewitt Logic Programs development illustrates Inconsistency Robustness by Hewitt Control structure issues in theorem proving by Hewitt ||- means "goal" (originated in Planner) by Hewitt ...	Hewitt	2014-01-01 18:30
Forum topic	John Shutt on "Abstractive Power" A programming language needs a model of computation by Hewitt	gasche	2013-12-25 04:25
Forum topic	Computation is not subsumed by deduction (contra claim by Kowalski) A message received exactly once is processed exactly once by Hewitt A goal is that a message sent is received exactly once by Hewitt The Actor Model is pure message passing by Hewitt	Hewitt	2013-12-23 17:45
Forum topic	Practical rules for controlling program effects in an imperative / OOP environment. What are concurency glitches in "Glitch" beyond overclaiming ;-) by Hewitt Managing concurrency effects is enormously challenging by Hewitt	bryanedds	2013-12-08 06:50
Forum topic	"Fog Cutter" model illustrates Actor Model issues Mailboxes (Fog Cutter) and Channels are "down the rabbit hole" by Hewitt Behavior is more general than Program+State by Hewitt	Hewitt	2013-12-04 00:15
Forum topic	Strong Mathematical Foundations for Computer Science Math is open; Math theories are closed by Hewitt 1st-Order Completeness is Weak v. Math Inferential Undecidablity by Hewitt Axioms versus Coq Defintions by Hewitt Absorption [P∧(P∨Q) = P] is not Inconsistency Robust by Hewitt Inconsistency Robust Boolean Equivalences by Hewitt Coq needs additional notation: functions vs. procedures by Hewitt Functions from ℕ into Boolean uncountable via standard proof by Hewitt First-order ZFC is an inadequate foundation for Computer Science by Hewitt Coq started as the calculus of inductive constructions by Hewitt ⊢ in additon to Boolean Equivalences by Hewitt ...	Hewitt	2013-11-25 14:58
Forum topic	actors conflate too much Relevant responses should be welcome even if delayed by Hewitt Every real system is networked and consequently large by Hewitt A list provides an ordering on its elements. by Hewitt Variable race conditions can be syntactically eliminated by Hewitt In practice, all information systems are large by Hewitt That a given server Actor always responds can be proved by Hewitt The Actor Model is abstract; you can fill in details by Hewitt Is the Actor Model the same as "dataflow concurrency"? by Hewitt Stacks, locks, coherent memory, etc: useful low-level mechanisms by Hewitt Threads are not a suitable foundation for concurrency by Hewitt ...	raould	2013-11-16 01:13
Forum topic	Why is Static Typing Hard? ? by Hewitt No difference between "static" and "dynamic" with type "Any" by Hewitt	Jon Purdy	2013-11-12 18:56
Forum topic	Continuation of Discussion: "Mathematics self-proves its own Consistency (contra Gödel et. al.)" Inconsistency Robustness is the emerging paradigm by Hewitt Is Pedagogical Logic capabable for inference in math? by Hewitt Is Pedagogical Logic suitable for practical reasoning? by Hewitt States can model nondeterminacy but not indeterminacy by Hewitt Requiring Instances in proof steps can be self defeating by Hewitt Theory of Cargo Cults by Hewitt Full Induction is not expressible in First-Order Logic by Hewitt State models of computation are inadequate for concurrency by Hewitt Tarskian Model Theory is inadequate for Computer Science by Hewitt First-order logic is inadequate for Computer Science by Hewitt	Hewitt	2013-10-26 19:36
Forum topic	Global State Machines Inadequate (contra Dijkstra and Gurevich et. al.) Implementing unbounded systems requires ever more resources by Hewitt Unfortunately I don't know date that CSP changed by Hewitt Unbounded nondeterminism in CSP by Hewitt Please see discussion of arbiters in "What is Computation?" by Hewitt Why did Hoare change CSP to unbounded nondeterminism? by Hewitt Petri Nets are a Global State Model by Hewitt Configurations versus Global States by Hewitt Bounded nondeterminism in CSP by Hewitt Plotkin proof: a global state machine has bounded nondeterminism by Hewitt	Hewitt	2013-08-14 18:34
first page previous page next page last page

---

Logs: Hack The Planet ; JavaLobby ; Daily Python-URL ; Daily WTF ; PHP everywhere ; (more)
Wikis: WikiWiki ; Erlang ; Common Lisp ; Haskell ; Squeak ; Tcl ; Program Transformation