[1/4] from: edoconnor::gmail::com at: 1-Sep-2005 17:15
This string processing exercise is taken from the post: http://discuss.joelonsoftware.com/default.asp?design.4.195596.22 Begin ////////////////////////// Given a text number of the follwing format: AH-1-1 Or AH-1-1G Or AH-1-G1 During data entry, we want the number code of the last part (token) to increment by one. So, if you pass the above values, you get AH-1-1 --> AH-1-2 --> AH-1-3 AH-1-1G --> AH-1-2G --> AH-1-3G AH-1-G1 --> AH-1-G2 --> AH-1-G3 ////////////// End I posted a REBOL version, but I'm not terribly gifted at writing parse rules. I'd be curious to see how other REBOLers might handle it. Of course, if you have an approach that is elegant and/or terse, reply to the orginal poster. Regards, Ed
[2/4] from: SunandaDH::aol::com at: 4-Sep-2005 3:29
> I posted a REBOL version, but I'm not terribly gifted at writing > parse rules. I'd be curious to see how other REBOLers might handle it.
Just saw your message this morning -- or some reason it's on the archive but didn't make it to my inbox. It's never clear just how much validation should be involved in an exercise like this. Should we be handling invalid cases where the last group does not contain a number? If the answer to that is no, then the code can be very simple - just need to find and increment the last string of digits. In fact, it can be simpler than below as my code is not a pre-parse solution. But it works, and that's usually as far as I take things. bump-id: func [id [string!] /local number number-copy digit digits ][ digit: charset "0123456789" digits: [some digit] id: head reverse id parse/all find id digit [copy number digits] number-copy: 1 + to-integer head reverse copy number replace id number head reverse form number-copy id: head reverse id return id ] Sunanda.
[3/4] from: tom::conlin::gmail::com at: 5-Sep-2005 15:24
ids: ["AH-1-1" "AH-1-1G" "AH-1-G1"] digit: charset "0123456789" else: complement digit rule: [any else here: copy n some digit there: (change/part :here 1 + load n :there) ] foreach id ids[parse find/last id "-" rule] print ids ; ids are in a block of strings ; incremented part is after last hyphen ; incremented natural numbers never get shorter On 9/1/05, Ed O'Connor <[edoconnor--gmail--com]> wrote:
> This string processing exercise is taken from the post: > http://discuss.joelonsoftware.com/default.asp?design.4.195596.22
<<quoted lines omitted: 21>>> To unsubscribe from the list, just send an email to > lists at rebol.com <http://rebol.com> with unsubscribe as the subject.
-- .... nice weather eh
[4/4] from: edoconnor::gmail::com at: 6-Sep-2005 11:33
Thanks Tom, and thanks to all who contributed. This exercise was very educational for me. Parse is one of those really powerful features that requires a lot of practice. Tutorial writers take note: Parse is a great double-feature; it's one of the great practical features of REBOL (text processing), as well as the gateway to creating domain-specific languages (little languages, mini-declarative languages, command and natural languages, etc.). If you want to show practicality + advanced power, Parse should probably be the keystone. Thanks again. Ed On 9/5/05, Tom Conlin wrote:
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