Re: Case insensitive lookfor()

[Søren Hauberg]

tor, 27 10 2011 kl. 20:07 -0700, skrev Rik:
> All,
> 
> I chanced upon an issue with the lookfor () command today.  I expected it
> to find the exact string I was looking for, but instead it uses search_str
> = lower (input_str).  Presumably this new search_str was meant to be
> compared against an all lower case version of the help string.  However,
> this is not what is in the doc-cache; only the true help text with
> capitalization is in the doc-cache.
> 
> Example:
> get_first_help_sentence ("ls")
> ans = List directory contents.
> lookfor ("List directory")
> <nothing>
> lookfor ("ist directory")
> ls                  List directory contents.
> 
> The lower() call makes it impossible to find certain keywords, often Matlab
> ones, which use mixed case such as "UniformOutput".  Offhand, I would vote
> for just removing the lower function call.  However, if everyone is really
> keen to have case insensitive matching then we could expand doc-cache to
> store a lower-case version of all of the help text.  This would double the
> current doc-cache size from 1.3 MB to 2.6 MB.

I think we, by default, should be making a case-insensitive search, i.e.
convert both help text and search term to lower case before comparison.
We don't have to store the help text in lower case to do this, we can
just convert it after loading it. It would then be nice to also be able
to do

  lookfor -case-sensitive my_search_term

which would disable any conversion to lower case. I think any
case-conversion can easily happen at run-time; no need to store anything
but the original text in the cache.

Søren