Re: pseudo-specs for a String class: tokenization

On Mon, 2008-09-08 at 23:52 +1200, Amos Jeffries wrote:

> >>>> I'd rather add a version whcih takes the String but not the delimiters.

> >>> I would recommend avoiding implicit conversions from String to anything
> >>> and I doubt there is a reasonable set of default delimiters.

> >> Why there would be an implicit conversion?
 
> > Ask Amos -- he has suffered enough from it to give an entertaining
> > answer :-). Or see the attached source file.
>
> All my failed attempts were broken the String MemBuf size separation. I
> was attempting to expand String to implicit conversion as-is but got
> hamstrung when memory buffers were cast to char* and the MemBuf data
> pointer were silently converted to String's and copy-allocator size
> asserts kicked in :-)
>
> This new method of attack should not encounter that due to two
> differences. Firstly the lack of a buffer size assert :-) and lack of
> need for an implicit conversion between the types.

Which emphasizes the original point that a Tokenizer constructor that
takes String but no delimiters is not needed and (because implicit
conversions, in general, have many negative side-effects) should be
avoided.

BTW, besides hard-to-find bugs, implicit conversions complicate
development because they make many compiler error or warning messages
confusing. The compiler tries the implicit conversion whenever it
should, and that often happens in places totally unrelated to the class
being silently converted to, which confuses many developers.

Cheers,

Alex.
Received on Mon Sep 08 2008 - 13:45:18 MDT