documentation is a tricky thing. I am pretty sure you do *not* want me to make doc changes.
I am very qualified to state exactly where I am getting confused and where it could be better. alas, if I tried to write it, I would write incorrect explanation, which would probably be worse. so, this needs one person who is learning it (the consumer) and one person who is teaching it (the producer). what we really need is the ability for readers to attach questions and notes to specific spots, that someone with knowledge can address later on at his/her convenience. the more specific the insertion point for comments is, the easier it will be for the writer of the documentation to fix this later. fwiw, I have written a textbook in corporate finance. I needed student reviewers that told me where they got confused. the material was obvious to me. I don't think there is any other way to make writing clear. in the absence of ability to change github to allow specific insertion points, I wonder if we want to branch the docs and request that comments be left in a particular color (say, red). regards, /iaw ---- Ivo Welch ([email protected]) http://www.ivo-welch.info/ J. Fred Weston Distinguished Professor of Finance Anderson School at UCLA, C519 Director, UCLA Anderson Fink Center for Finance and Investments Free Finance Textbook, http://book.ivo-welch.info/ Exec Editor, Critical Finance Review, http://www.critical-finance-review.org/ Editor and Publisher, FAMe, http://www.fame-jagazine.com/ On Mon, Jan 5, 2015 at 2:35 AM, Sean Marshallsay <[email protected]> wrote: > Hi Ivo > > You're more than welcome to contribute to the documentation yourself to help > clarify anything you found confusing. > > Regarding your second point, open() does not return a named type it returns > a tuple containing some kind of stream and some kind of process, Pipe is > some kind of stream and Process is some kind of process. Hopefully the > following code snippet will help clear things up. > > julia> x = open(`less`) > (Pipe(closed, 0 bytes waiting),Process(`less`, ProcessExited(0))) > > julia> y = typeof(x) > (Pipe,Process) > > julia> typeof(y) > (DataType,DataType) > > help?> issubtype > INFO: Loading help data... > Base.issubtype(type1, type2) > > True if and only if all values of "type1" are also of "type2". > Can also be written using the "<:" infix operator as "type1 <: > type2". > > julia> issubtype((Base.Pipe, Base.Process), (Base.AsyncStream, > Base.Process)) > true > > help?> super > Base.super(T::DataType) > > Return the supertype of DataType T > > julia> super(Base.Pipe) > AsyncStream > > julia> super(Base.Process) > Any > > So what we can see is that open() does return a (stream, process) tuple but > stream should actually be called AsyncStream and process should actually be > called Process. > > Hope this helps > Sean > > > On Monday, 5 January 2015 06:59:31 UTC, ivo welch wrote: >> >> >> I am reading again about the type system, esp in >> http://julia.readthedocs.org/en/latest/manual/types/ . I am a good guinea >> pig for a manual, because I don't know too much. >> >> a tuple is like function arguments without the functions. so, >> >> mytuple=(1,"ab",(3,4),"5") >> >> is a tuple. good. >> >> what can I do with a typle? the manual tells me right upfront that I can >> do a typeof(mytuple) function call to see its types. good. >> >> alas, then it goes into intricacies of how types "sort-of" inherit. I >> need a few more basics first. >> >> I would suggest adding to the docs right after the typeof function that, >> e.g., mytuple[2] shows the contents of the second parameter. the julia cli >> prints the contents. the examples would be a little clearer, perhaps, if >> one used a nested tuple, like (1,2,("foo",3),"bar"). >> >> before getting into type relations, I would also add how one creates a >> named tuple. since open() does exactly this. well, maybe I am wrong. the >> docs say it returns a (stream,process), but typeof( open(`gzcat d.csv.gz`) >> tells me I have a (Pipe,Process). >> >> I know how to extract the n-th component of the open() returned tuple >> (with the [] index operator), but I don't know how to get its name. x.Pipe >> does not work for open(). >> >> well, my point is that it would be useful to add a few more examples and >> explanations here. >> >> regards, >> >> /iaw >> >
