[Tutor] Nested for loops, possibly?

[Bob Williams]

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On 05/02/15 18:46, DaveA wrote:
> You don't need much class understanding at all for this.  Something
> like:
> 
> class Job: def __init__(self, retain, srcpath, suffix, syncpath,
> snappath, ...): self.retain = retain = datetime.timedelta  (days =
> retain) self.srcpath = os.path.join (srcpath, suffix) self.syncpath
> = os.path.join  (....
> 
> Notice that in the above method,  the object is called self, while
> in the loop in main it'll be called job, or whatever you use as a
> loop variable.
> 
>>> 
>>>>> The class would hold retain, srcpath, syncpath, snappath,
>>>>> etc. And your list would have 7 instances of that class
>>>>> currently, corresponding to your doc, pic, misc, ...
>>>>> 
>>>>> That list would be THE global, replacing these 35 or so. It
>>>>> would be populated something like:
>>>>> 
>>>>> def initialize (worklist=[]): worklist . append  (Job (90, 
>>>>> src_path, "Documents", "documents", "docsnaps") worklist
>>>>> .append (Job (90, src_path,  "Pictures", ... .... return
>>>>> worklist
> (Reformatting )
> 
> def initialize (worklist=[]): worklist . append  (Job (90,
> src_path, "Documents", "documents", "docsnaps") worklist
> .append(Job (90, src_path,  "Pictures", ... .... return worklist
> 
>>>>> 
>>>>> Now all the joins and globs are done in the Job
>>>>> initializer, just once.
>>>>> 
> 
> 
>>>>>>> 
>>>>>>> def main(): print("Backing up ", src_path,
>>>>>>> "/Documents\n", sep='') do_sync(doc_srcpath,
>>>>>>> doc_syncpath) create_snaps(doc_syncpath, doc_snappath)
>>>>>>> print("Documents backup completed.")
>>>>>>> expire_snaps(doc_snaplist, today, doc_retain)
>>>>> 
>>>>> At this point main becomes something like
>>>>> 
> def main (): jobs = initialize () for job in jobs: do_sync
> (job.srcpath, job.syncpath) create_snaps (job.syncpath,
> job.snappath) expire_snaps (job.snaplist, ...
> 

Thanks, that formatted nicely, and is a nice clear explanation.

Bob
- -- 
Bob Williams
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