Why don't you manage None values in int_to_hms function?
Il giorno giovedì 25 ottobre 2012 21:56:17 UTC+2, Joe Barnhart ha scritto: > > Actually Paolo, I have a custom Validator which contains the formatter > function. It is supplied automatically when I use the validator, so I do > not get a chance to change its calling sequence as you show in the case of > using "represents". Here is the validator class: > > class IS_ELAPSED_TIME(object): > def __init__(self,error_message='Must be MM:SS.hh or MMSShh (with no > punctuation)'): > self.error_message=error_message > def __call__(self,value): > try: > if value and value.upper() != 'NT': > res = hms_to_int(value) > else: > res = None > return (res,None) > except: > return (value,self.error_message) > def formatter(self,value): > if value: > rtn = int_to_hms(value) > else: > rtn = 'NT' > return rtn > > Since the Field is declared to use this validator, I have no explicit > "formatter=" statement I cannot easily employ your solution. I do not > understand why "None" is not allowed to be formatted in the first place. > > -- Joe B. > > On Thursday, October 25, 2012 6:07:09 AM UTC-7, Paolo Caruccio wrote: >> >> or better >> >> def format_function (value) >> formatted_value = ..... >> return formatted_value >> >> db.tablename.fieldname.represent= lambda value,row: format_function(value >> ) if value else "Not Standard Time" >> >> >> >> >> Il giorno giovedì 25 ottobre 2012 13:31:43 UTC+2, Paolo Caruccio ha >> scritto: >>> >>> Did you try: >>> >>> db.tablename.fieldname.represent= lambda value: value if value else 'NT" >>> >>> ? >>> web2py book reference >>> http://web2py.com/books/default/chapter/29/06?search=represent#Record-representation >>> >>> >>> Il giorno giovedì 25 ottobre 2012 03:20:29 UTC+2, Joe Barnhart ha >>> scritto: >>>> >>>> I have an application where I expect "None" items in my database and I >>>> want to format them to "NT". It is an app that uses time standards, and >>>> if >>>> there is no standard present I expect a "None" in the database which >>>> translates to a field of "No Time" or "NT". >>>> >>>> The problem is that the current implementation of formatter in the >>>> Field class tests the value for "None" and escapes before the formatter is >>>> called. >>>> >>>> I can see why this behavior might be expected in a lot of cases, but it >>>> seems extreme to deny the ability to format "None" into a more pleasing >>>> form for those applications that could benefit from it. Here is the >>>> offending part of formatter (located in gluon/dal.py): >>>> >>>> def formatter(self, value): >>>> requires = self.requires >>>> if value is None or not requires: >>>> return value >>>> >>>> If I change the above to: >>>> >>>> def formatter(self, value): >>>> requires = self.requires >>>> if not requires: >>>> return value >>>> >>>> I get my desired behavior, which is to pass "None" to my formatter >>>> which is implemented as part of a custom Validator object. I realize the >>>> code now has to go "further" for cases where the value is None, but is it >>>> really safe to assume nobody will ever want to "format" None into another >>>> string? Not in my case, at least! >>>> >>>> Joe B. >>>> >>>> >>>> --
