rx use case for ETL (was: Looking for generic text transformation utility library)

[Van L]

>> I can't seem to find a way to do simple
>> programmatic transformations without writing
>> a good portion of code
> 
> "generic text transformation utility", you mean
> like the Unix tool sed(1), the "stream editor
> for filtering and transforming text", or tr(1),
> to "translate or delete characters"?
> 
> Can you provide me/us with an example of
> a text, as well as the end result you want it
> to be translated into?

A killer-mode in Emacs for the 
Extract Transform Load (or ETL) industry would be 
for a way to use rx (not regexp) to step by step 
transform a source buffer to desired target form.

Step 1. begin with two buffers, the source and target
which are identical

Step 2. an rx machine assisted composition buffer does
what sed(1), tr(1), regexp do by showing in two mini buffers
candidate patterns for source to target change which are 
easy human readable and writable; imagine this kind of 
workload isn’t done more than four times each year so 
the readability has to be there after long stretches
and for first timers

Step 3. stop when there are no 
undesired outliers in the target form