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Re: bug report dispute resolution request



On Wed, Dec 13, 2000 at 06:59:54AM -0500, Raul Miller wrote:
> On Wed, Dec 13, 2000 at 07:46:22PM +1100, Herbert Xu wrote:
> > Here is what the SuS says (AFAIK POSIX says the same thing):
> > 
> > Token Recognition
> > 
> > ...
> > 
> >          5.If the current character is an unquoted "$" or `, the shell
> >          will identify the start of any candidates for parameter
> >          expansion, command substitution, or arithmetic expansion
> >          from their introductory unquoted character sequences: "$"
> >          or ${, $( or `, and $((, respectively. The shell will read
> >          sufficient input to determine the end of the unit to be
> >          expanded (as explained in the cited sections).
> 
> Looks to me as if SuS indicates that the above is suppose to happen
> before:

Well, there is no way to identify the end of the unit unless you recurse
as you read the characters.  For example, in

$( echo $(( 3 + 3 )) )

You have to recurse when you reach $(( or you will wrongly consider the first
) to be the end of the command substitution.

> >          While processing the characters, if instances of expansions
> >          or quoting are found nested within the substitution,
> >          the shell will recursively process them in the manner
> >          specified for the construct that is found. The characters
> >          found from the beginning of the substitution to its end,
> >          allowing for any recursion necessary to recognise embedded
> >          constructs, will be included unmodified in the result token,
> >          including any embedded or enclosing substitution operators
> >          or quotes. The token will not be delimited by the end of the
> >          substitution.
> 
> Otherwise, why use the word "candidates"?

The word is only used as a placeholder here and has no particular bearing
on the issue at hand.
-- 
Debian GNU/Linux 2.2 is out! ( http://www.debian.org/ )
Email:  Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt



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