[PyQt] Trying to learn ...

[Hans-Peter Jansen]

Dear BigAl,

On Wednesday 03 August 2011, 01:27:55 Algis Kabaila wrote:
>
> Hi, Pete!
>
> Looking at testui.py it seems to me that it should/would work without
> the decorator @pyqtSlot().  This suggests two questions:
>
> 1. What is the advantage, if any, to use the decorator in this case?

In short: none. I opted to mangle Magnus' file in a minimum invasive 
fashion, and @pyqtSlot was one weapon in his quest to get the thing 
behave... 

IMHO, after getting used to it, it's usefulness is two fold: it nicely 
documents the slots in your classes, and helps to disambiguate/fix 
those cases, were it is needed. E.g. there are some not so obvious 
cases in esoteric usage pattern of webkit with javascript/PyQt 
interaction:

http://www.riverbankcomputing.com/pipermail/pyqt/2010-November/028600.html

> 2. Where could one look up the code for this decorator?

http://www.riverbankcomputing.com/static/Docs/PyQt4/html/new_style_signals_slots.html#the-pyqtslot-decorator

> Thanks for your forever careful care of "simple" questions - there is
> nothing simple when one does not know how to get it working!  Good
> work!
>
> OldAl.

I dimly remember my own PyQt quest ten years ago. ;-)

BTW, I talked to someone lately, who was involved in a web based ERP 
system in about the same time span. Finally, they've given up, since 
they failed to cope with the need to redesign/rewrite the whole thing 
for the third time (in order to deal with the 
html/java/javascript/browser evolution).. I cannot qualify their 
development process, but I imagine, that sustainability of PyQt code is 
a couple of magnitudes above that level, even if factoring in sip v2 to 
v4, (Py)Qt v3 to v4 and python v2 to v3 advancements from that time.

Pete