[Os-project-managers] ticket 14 - question about programming style

[Horand Gassmann]

Hi guys,

quick progress report: I managed to write a new class OSOutput, which  
contains the private Printf method that generates all of our output  
along with an array of the output files and devices that are currently  
defined.

So I have in the OSSolverServices main the following code:

     OSOutput *osoutput = new OSOutput();
     std::string versionInfo = OSgetVersionInfo();
     osoutput->OSPrint(ENUM_OUTPUT_AREA_main,  
ENUM_OUTPUT_LEVEL_always, versionInfo);

This puts the version info into stdout as well as any other files that  
might have been defined bu the user.

However, I now have to make sure that the single instance osoutput is  
visible in every method so I can process further output.

The way I see it there are three possibilities, each with its own drawbacks.

1. I can declare the instance as a global variable. I don`t like to do that.

2. I can set up a namespace, so that the variable is visible from  
everywhere within the namespace. This is what Andreas does in Ipopt,  
but I read that it is frowned upon, essentially for the same reason  
that global variables are deprecated.

3. I can pass the instance as an extra argument to all methods that  
use output (which is basically every routine we have ever written). As  
far as I can see, this is clean, but it is cumbersome, and it blows  
the API sky-high.

Any advice for me?

Cheers

gus
-------------------------------------------------------

Horand I. Gassmann, Professor

Kenneth C. Rowe School of Business, Dalhousie University
6100 University Avenue, PO Box 15000
Halifax, Nova Scotia, Canada, B3H 4R2
ph. (902) 494-1844
fax (902) 494-1107

http://myweb.dal.ca/gassmann/