Re: st: macro problem

[Jeph Herrin <stata@spandrel.net>]

There is no problem with -strpos-, which never returns missing and which 
is zero exactly when I want it to be. The problem was in creating the 
original macro and then referencing the elements so that they appear in 
-strpos- with the correct number of quotations marks; I was achieving 
either too many or too few of the latter.

The solution (or at least, a solution) is for local -matchlist- needed 
to be enclosed in compound quotes, and then ditto the reference:

   local matchlist `""string 1" "string 2" "string 3" .... "string 55""'

   gen byte match=0
   foreach S of local matchlist {
        replace match = 1 if strpos(strvar,`"`S'"')
   }


The reference in -strpos- looks wrong to me - I would anticipate that 
`S' would include the necessary "'s for -strpos-, but it does not. 
Without the extra quotes on the original local, however, `"`S'"' 
resolves to include too many "'s.

cheers,
Jeph


Otherwise,

On 6/11/2012 11:58 AM, Richard Goldstein wrote:
> you don't make it clear about what doesn't work
>
> but here is a guess: you are getting match=1 in all cases (or at least
> all where strvar is not missing); remember, however, that strpos=0 if
> "S" is not found; so, in addition to the quotes, etc., I guess you want
> to ensure that strpos is>0 (and maybe<.)
>
> Rich
>
> On 6/11/12 11:50 AM, Jeph Herrin wrote:
> > This should be trivial, but for some reason I cannot get it.
> >
> > I have a string variable, and I have a list of string values I need to
> > match against it. There are occasional trailing or leading characters in
> > the variable, so I am using -strpos- to find matches. Thus
> >
> >    local matchlist "string 1" "string 2"  "string 3" .... "string 55"
> >
> >    gen byte match=0
> >    foreach S in `matchlist' {
> >          replace match = 1 if strpos(strvar,`S')
> >    }
> >
> > Now, I know I have got the quotes and macro evaluations wrong, but that
> > is the problem: I've tried this many different ways, and yet cannot seem
> > to find a combination that works. Any thoughts?
> >
> > thanks,
> > Jeph
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