Re: [haskell] the One Big Monad problem

Christopher Jeris wrote: > > A while ago someone mentioned the problem of several monads tending to > coalesce into one big monad, and alluded to a solution to this problem > called "monad transformers". I am struggling with this now in some code > that I am trying to sketch out. Could someone

Re: parsing arithmetic. Reply.

Mon, 8 Nov 1999 13:49:39 +0300 (MSK), S.D.Mechveliani <[EMAIL PROTECTED]> pisze: > as *any* Haskell compiler understands the programs with the > expressions like > "2 + 3 * 2", > is not it natural to provide a standard function for parsing > of such

RE: A datatype for the text editor buffer?

I wrote: > I have never seen anyone use the technique in any distributed Haskell code. > Gerard Huet wrote the article that appeared in JFP, and I believe he > remarked that they had used the technique to represent ASTs in a structural > editor (perhaps in the Coq distribution?). Sorry, let me im

Re: A datatype for the text editor buffer?

> "George" == George Russell <[EMAIL PROTECTED]> writes: > You need random access into the strings, or else how am I going to search > for all occurrences of "wombat" in columns 50-59, or how indeed is the > Boyer-Moore algorithm going to be implemented? I dunno 'bout that. I'

RE: A datatype for the text editor buffer?

> > The Zipper technique is the generalization > > of this idea to arbitrary algebraic datatypes; it can be generalized to > > higher-order data too (continuations). I was too optimistic when I wrote this; someone actually e-mailed me asking for a fuller explanation after I posted thi

Re: A datatype for the text editor buffer?

Peter Hancock wrote: [snip] > To improve performance, I thought one can represent line structure. I > think that the original editor just represented the text by a > character sequence with a cursor, where \n was among the characters. > Here one could have a line sequence with a cursor, and a cha

Re: Thanks, and new question re existensials

On 08-Nov-1999, Simon Peyton-Jones <[EMAIL PROTECTED]> wrote: > [someone wrote:] > | I wonder why it was hard in GHC? > > It wasn't hard. We're currently in the process of implementing existential types in Mercury. Whenever we make a change, we record how long (roughly) we think it took us to m

RE: A datatype for the text editor buffer?

> "Frank" == Frank A Christoph <[EMAIL PROTECTED]> writes: > Peter Hancock wrote: >> > "Marcin" == Marcin 'Qrczak' Kowalczyk <[EMAIL PROTECTED]> writes: >> >> > What do you think would be the best representation of the buffer for >> > such a crazy idea as a text edito

parsing arithmetic. Reply.

Luis Manuel O.Soares <[EMAIL PROTECTED]> writes to: [EMAIL PROTECTED] > [...] > I would like a function that deals with things pretty much like > this one: > f ("2 + 3 * 2") = 8 The DoCon-2 program does the things like let p1 = cToUPol

RE: Thanks, and new question re existensials

| Which is what we did in Hope+C (you have to say it out loud | ;-)) as well. Yes it was, and all credit to you for doing it then. hbc followed suit some years ago. GHC and Hugs are latecomers. | So that's good, I was concerned my earlier answer and | reference to a paper on implementation wa