Re: [nmap-svn] r36162 - nmap/nselib/data

[Patrick Donnelly <batrick () batbytes com>]

On Mon, Aug 22, 2016 at 1:33 PM, nnposter
<nnposter () users sourceforge net> wrote:
> > The other option you mentioned directly to me was: local _, openssl =
> > pcall(require, "openssl"); This option should not be used, since "_" is
> > considered a throwaway variable name; It could easily be overwritten,
> > and code that tests it doesn't make sense. So it would open us up to
> > crashes when someone writes unconditional code that tries to index the
> > nonexistent openssl library.
>
> I do not believe that my example...
>
>     local _, openssl = pcall(require, 'openssl')
>     ...
>     if openssl and openssl.md5 then
>
> ...had any dependency on "_", namely there was no explicit or implicit
> "code that tests it", so I am not quite sure that I understand your point.
>
> To satisfy my curiosity, could you please point out what specifically
> would be wrong with the example? (To make it clear, I am not opposed to
> option #3; I have used it in the original commit after all. I am just
> trying to understand the pitfalls with option #4.)

You could also do this to avoid creating the _ variable:

local openssl = select(2, pcall(require, "openssl"))

(I have no strong opinions on any of the options...)

-- 
Patrick Donnelly
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