The most underrated feature in Python 3

http://blog.ionelmc.ro/2014/08/03/the-most-underrated-feature-in-python-3/

by edward • 11 years ago

96 17 11 years ago

blog.ionelmc.ro

santiagobasulto• 11 years ago

Great post. I'm a python dev and had never noticed that.

aurelianito• 11 years ago

Java had this feature since the last millenium (java 1.3, i think). I really miss it programming in python 2.7.

MrBuddyCasino• 11 years ago

For anyone wondering: its chained exceptions.

Latty• 11 years ago

Python's is actually a little nicer too, in 3.x - it has two types of chains, the 'root cause' one like Java, and a 'this is what I was handling when this exception happened' - to stop an error in your exception handling code hide the original error.

pacofvf• 11 years ago

by reading this I just learned about the concept of chained exceptions, although I can't see why is so useful, the built-in traceback and sys module has always been good enough:

    import sys,traceback
    try:
        ...
    except Exception as ex:
        exc_type, exc_value, exc_traceback = sys.exc_info()
        logger.error("%s:%s" % (str(ex),  str(traceback.format_exception(exc_type, exc_value, exc_traceback))))
        raise MyException(" :( ")

baq• 11 years ago

that's not nearly good enough, it's barely acceptable. i've been programming python for a decade and the fact you have to do this with exceptions was plainly dumb. as a programmer you should never have to worry about preserving tracebacks.

sylvinus• 11 years ago

Sad to see this PEP dates back to 2005, and 10 years later the majority of Python developers are still on 2.x and don't benefit from it :-/

lmm• 11 years ago

I think the majority are using 3.x for new projects? Of course there's still a lot of 2.x around.

jahnu• 11 years ago

A lot of us who came to Python late have only ever used 3. I can't imagine the horror of dealing with multiple charsets and bytes in 2.x

mrkmcknz• 11 years ago

3years ago I would probably argue that you should just use Python 2.X. But most packages you will use are now ported to Python 3.

theVirginian• 11 years ago

One issue is that almost every google search for documentation points to the 2.x version, sometimes even if you search for Python 3 meaning you have to manually find the dropdown and switch to a new version. I imagine this is cumbersome for many new developers.

yuvadam• 11 years ago

It's all about what OSs ship with, and we're getting to the point where Python 3.x is the default.

AndrewOMartin• 11 years ago

I may be just a bit tired right now but I had to keep nipping to the top of the article to remind myself which was foo and which was bar.

There are good times to use foo and bar, rather than more self-documenting style placeholder names, but this was not one of them for me.

xahrepap• 11 years ago

I had the same problem. My first thought was, why can't we just name them something like 'dependency' and 'app' or whatever. So much clearer.

rprospero• 11 years ago

Similarly, the author's definition of foo.py does not seem to actually define functions d, e, and f as referred to the traceback. That confused me for a bit.

The most underrated feature in Python 3

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