Re: saved from prince of eval

[Ray Andrews <rayandrews@eastlink.ca>]

On 11/09/2015 10:41 AM, Bart Schaefer wrote:
>     IN[PAGE]=${${(P)IN[list]}[IN[topE],IN[bottomE]]}
>
Thanks.

I've realized that my friend '(e)' was with the Enemy all along.  I have 
a function that prints out a half sane modification of 'set', and sure 
enough:
> }      foo="\$${IN[list]}[${IN[topE]}, ${IN[bottomE]}]"
> }      IN[PAGE]="${(e)foo}"
Ended up 'evaling'  the content and doubling the size of my environment 
every time it was run.  It's seems strange tho, how can a parameter be 
set twice (or 16 times) to exactly the same value? But your line above 
seems, finally,  to do what it's asked to do without evaling anything.

Speaking of which, we have 'env' which only gives us the--don't know the 
proper term--lowest level system stuff. And we have 'set' which gives us 
everything including the kitchen sink.  So I have this:

    #1) strip out the color.
    #2) cut lines down to 80 chars (some are a thousand).
    #3) select only things that are probably variables.
    eenv ()
    {
         set |
         sed -r "s/\x1B\[([0-9]{1,2}(;[0-9]{1,2})?)?[mGK]//g" |
         sed 's|^\(.\{1,80\}\).*|\1|' |
         grep --binary-files=text '='
    }


... which is an effort to display just the current parameters. However 
the output refuses to open in any of my editors if piped to a file, they 
all think it's binary.  Looking at it in hex, I see that it's a soup of 
backslashes and single quotes. Why is that?  Is there a civilized way of 
listing all current parameters that's just plain text, no backslashes?  
Not knowing the hierarchy, perhaps even avoiding those deep things like 
'color=' which isn't something one wants to look at very often--those 
deep internal things that have nothing to do with the user.  It would be 
a useful thing.