[lug] REGEX DEVELOPMENT TOOL
tkil at scrye.com
Tue May 14 14:05:29 MDT 2013
Gordon Golding <gordongoldin at aim.com> writes:
> Legacy systems send info - client info, transactions, info about
> suppliers for the transaction, etc.. in packed text files. Basic
> structure is known, but there are so many variants, even from one
I agree with another poster earlier in the thread that you probably
want to split this into two halves: first, normalize all messages into
a single unified format (can be XML or whatever); second, process that
That is, don't try to embed parsing logic into your processor:
structure your solution into two pieces (parser/normalizer and then
(In the heavy iron world, the first step is known as "ETL": extract,
transform/translate, load. The idea is to take whatever particular
input you're given, transform it to a standard format, then load it
into a database representation of that standard format. After the
data is loaded, the business logic works only with the data in the
> So there needs to be a flexible library of regexs which can be
> re-used and extended.
It's not clear exactly what you mean by "extended" here.
As for "re-use", most regex-wielding languages allow for one regex to
be embedded in another, or for two regexes to be concatenated.
> Are there any tools better than regex? Like a powerful parser tool
> - like the front end of a compiler?
lex or flex, then yacc or bison.
Both are substantially more complicated than "just regex" (although
the former tend to rely on regexes in the first place.)
> What about the best tool to develop and manage a tree of Regexs?
If you really can organize all your input as a tree of regexes, then
you might very well want to try the flex/bison route.
> Like the way a code management system gives you the tree - I could
> see the parents and siblings and easily see differences, so I could
> easily visualize and grab "this from branch A and this from C and
> quickly create my hybrid".
I don't know of any GUI that will do what you want.
As a start, I would recommend creating a simple library of regex
"atoms" that match the lowest-level items in your data stream; then
you can concatenate them to handle a particular stream of data.
If this is still not clear, a few examples of the kind of input (and
variation in input) that you're seeing would probably let us help you
p.s. No need to shout... all caps is rarely necessary.
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