Re: line continuation with sed

[Ray Andrews <rayandrews@eastlink.ca>]

On 2022-10-14 19:34, Aaron Schrab wrote:
> Instead I'll give a method to help avoid the problem. For awhile now, 
> anytime I'm using calling a command with enough options to warrant 
> line continuation I build them up in an array instead. This allows 
> splitting across lines without using a backslash at the end, and 
> *actually* allows comments.
>
> This also allows the arguments to be build up gradually with some 
> being added conditionally.
>
> The below actually works as written including the comments:
>
>     args=(
>       -re 's/abc/xyx/' # End of the alphabet is better
>       -re 's/123/456/' # Bigger numbers are better
>       # -re 's/foo/bar/' # Disable for now
>     )
>
>     if [ -r /some/file ]
>     then
>       args+=(-re 's/new/old/')
>     fi
>
>     echo abc123 | sed "${args[@]}"
>
> For zsh you can just use $args to reference it, the way I wrote it 
> above will work in bash as well.
>
That is most clever!  As it is, when I have a long set of seds, I copy 
the whole thing, comment it, and then add comments (within the comments) 
so as to inform myself what the seds are doing since I tend to forget 
all the syntactic details. You method permits the comments where they 
naturally belong.  Mind, it seems to me that comments after a line wrap 
would be easy to implement but that's not what we have.  Thanks again.