D2 is really that stable as it is claimed to be?

[Michel Fortin]

On 2013-09-22 01:45:33 +0000, Walter Bright <newshound2 at digitalmars.com> said:

> On 9/21/2013 6:09 PM, Sean Kelly wrote:
>> A single pointer per file isn't much memory and a write per line isn't much
>> of a speed hit. Fair point about holding the file in memory except that DMD
>> does this anyway. Mine wasn't a general comment so much as one specifically
>> about the D front end. As for the rest, if you can see the problems with an
>> approach before starting then don't do it that way. :-)
> 
> It isn't once per file, it's once per node in the AST, plus all the 
> copying around of the value(s).

You could *replace* the line number with a "byte from start of file" 
and then compute lazily either the line number or the column number for 
the rare times where you actually need to get the line or column 
number. (Ideally you'd also keep a map of the byte offset for the start 
of each line in a file to make that computation fast.)

Column values are of interest in an IDE because it can pinpoint the 
error more precisely. The IDE can show exactly where the error is (for 
instance with a dotted red underline), often allowing you to fix the 
error without even reading the error message (especially when it's a 
typo). With a background-compilation-as-you-type system you know almost 
immediately when you make an error, and you know where it is.

I do agree that it is of minor interest when you're reading the error log.

-- 
Michel Fortin
michel.fortin at michelf.ca
http://michelf.ca