Re: help with pretty printing

On Jun 7, 2012, at 3:42 AM, Joachim Protze wrote:

> On 01.06.2012 11:07, somersetgraham wrote:
>> def build_dictionary ():
>>    pretty_printers_dict[re.compile ('^QFile$')] = lambda
>> val:QFilePrinter(val)
>>    pretty_printers_dict[re.compile ('^QFile *$')] = lambda
>> val:QFilePrinter(val)
> you may try something like the following to match both cases:
> 
> pretty_printers_dict[re.compile('^QFile ( \*)?$')] = lambda
> val:QFilePrinter(val)
> 
> 
> The asterisk is a special character in regular expressions and has to be escaped to match an asterisk. Your
regexp matches QFile with any count of spaces as postfix.
> 
> - Joachim

Yes, but since you're dealing with a regular (not raw) string here, the \ needs to be doubled, otherwise it is
treated as a string character escape instead of a backslash character inside the string.  So one of these
will match space followed by asterisk:

pretty_printers_dict[re.compile('^QFile ( \\*)?$')] = lambda val:QFilePrinter(val)
pretty_printers_dict[re.compile(r'^QFile ( \*)?$')] = lambda val:QFilePrinter(val)