Re: [Help-bash] Understanding read -r

[Dan Douglas]

On Friday, October 05, 2012 05:16:13 PM Chet Ramey wrote:
> On 10/4/12 6:58 PM, Dan Douglas wrote:
> 
> > As an aside, mksh has an interesting syntax to assign a heredoc result 
directly to a variable:
> > 
> > # mksh
> > 
> > var=<<EOF
> > ...
> > EOF
> > 
> > This is optimized to happen in memory with no temporary file.
> 
> Is that anything more than syntactic sugar? It doesn't seem different
> enough from multi-line double- or single-quoted strings to make it worth
> adding.

It's not the greatest choice of syntax considering x=<<EOF is already a valid 
simple command. There would have to be a POSIX mode exception, and I can't 
imagine how many of dark corners would be introduced by supporting it for all 
assignments in general.

Better would be to add a type of quoting for specifying string literals 
without concern for nested quotes or escapes, especially for strings that are 
code. Abusing the heredoc as a form of quoting is too messy for interactive 
use, only slightly less messy in a script, and not quite the right thing when 
all you really want is to inject a string someplace without the shell touching 
it.
--
Dan Douglas