repost of alike 'missing a way to extract data'

[Alex fxmbsw7 Ratchev]

as i got suggested here for help-bash for new ..

there is ways to crop data to wanted by cropping the excludes out
but where is the simple way of keeping matching

i'd say implent backtrack references for @( .. ) etc groups

pseudo exmaple

declare -A big=( mess of data )
var=$( declare -p big )

now to extract the elements, beware with mess of data i dont mean 'mess'
'of' 'data'

it needs to parse either no quotes, $' quotes or " quotes
from beginning to end

as greycat suggested, .. any idea ?
im not looking for bad hacks or so
actually more like adding demandant important stuff to bash's functionality

such as regexes and back-references for groups

.. no war make peace want war ? war the non peace