[OSM-dev] Think I've found the renderer bug

[Lars Aronsson]

Nick Whitelegg wrote:

> Testing on the dev server, I think I've found the bug that's 
> causing the non-rendering of ways properly. [...]

>         segs << [row['segment_id'].to_i] <-- HERE
>           way.segs.each do |segid|
>               @tagged_segments[segid.id.to_i].style = 
> @rules.get_style(way.tags) unless way.tags.nil? or 
> @tagged_segments[segid.id.to_i].nil?

This is where my old knowledge of half a dozen programming 
languages from Fortran to Perl doesn't really help me.  In most 
cases I can read sourcecode and spot algorithmic errors, but I 
would really need to take a crash course in Ruby syntax.  Does 
"<<" mean the same as in C++, does "@" mean the same as in Perl, 
and was the "?" on the last line part of Nick's question or part 
of the sourcecode?

What I can see from dao.rb and many other files is that they are 
not much commented, and there really is no other technical 
documentation.  This is a sign of too few programmers having 
looked at the code, which increases the risk for blunders.

I always recommend reading source code as a social activity, even 
if you don't intend to modify it.  Is anybody interested in 
joining a "reading circle" for OSM sourcecode and could the dev 
list be used for this?  A good definition is given here, 
http://www.sil.org/lingualinks/literacy/ReferenceMaterials/GlossaryOfLiteracyTerms/WhatIsAReadingCircle.htm 
only that I want to apply the concept to sourcecode rather than 
literature.


-- 
  Lars Aronsson (lars at aronsson.se)
  Aronsson Datateknik - http://aronsson.se