Re: print color escapes

[Ray Andrews <rayandrews@eastlink.ca>]

On 12/31/2014 10:35 PM, Bart Schaefer wrote:
> torch% print -r ${(V)fg[cyan]}
> ^[[36m
> torch% print -r ${(q)fg[cyan]}
> $'\033'\[36m
Thanks, either is usable.

} I'd expect 'print } -r' to 'stay literal' with the expanded variable 
but no luck.

 > It is staying literal with the expanded variable. The variable has a 
literal escape (ascii 033) in the value, not the string backslash e, so 
print -r emits that literal escape etc. It's the terminal that then 
turns that into a color, not the print command.

Ok, we hafta stop the terminal from doing it's thing when we want to 
'see' the escape code without the terminal 'doing' the escape code. But 
why/where is the change made?  I tried this script:

    cyan='\e[36;1m'
    norm='\e[0m'
    print    "1: $fg[cyan] howdy $norm"
    print    "2: $cyan howdy $norm"
    print -r "7: the value of fg[cyan] is: ${(V)fg[cyan]}"
    print -r "8: the value of cyan       is: ${(V)cyan}"


    1:  howdy << nicely cyan
    2:  howdy << nicely cyan
    7: the value of fg[cyan] is: ^[[36;1m      << modified to 'bold' by me.
    8: the value of cyan       is: \e[36;1m

... either the " \e[ " or the " ^[[ " form produces the color change, so 
why does the 'color' function 'bother' to change from one form to the 
other, and how/where?  I see the escape created like this:

     local lc=$'\e[' rc=m

... so how does it end up like: " ^[[ " ?

BTW I know you can't type " ^[[ " and have it work, the " ^[ " 
represents the escape code but can't create it, so I know it's a 'safe' 
way of showing the code, but since both my '$cyan' and 'fg[cyan]' seem 
to work the same way,  I'm confused as to what the point of the 
difference is.