Why doesn't Python (error msg) tell me WHAT the actual (arg) values are ?

[Peter J. Holzer]

On 2023-02-25 09:10:06 -0500, Thomas Passin wrote:
> On 2/25/2023 1:13 AM, Peter J. Holzer wrote:
> > On 2023-02-24 18:19:52 -0500, Thomas Passin wrote:
> > > Sometimes you can use a second parameter to assert if you know what kind of
> > > error to expect:
[...]
> > > With type errors, assert may actually give you the information needed:
> > > 
> > > > > > c = {"a": a, "b": 2}
> > > > > > assert a > c
> > > Traceback (most recent call last):
> > >    File "<stdin>", line 1, in <module>
> > > TypeError: '>' not supported between instances of 'list' and 'dict'
> > 
> > Actually in this case it isn't assert which gives you the information,
> > it's evaluating the expression itself. You get the same error with just
> >      a > c
> > on a line by its own.
> 
> In some cases.  For my example with an explanatory string, you wouldn't want
> to write code like that after an ordinary line of code, at least not very
> often.  The assert statement allows it syntactically.

Yes, but if an error in the expression triggers an exception (as in this
case) the explanatory string will never be displayed.

        hp

-- 
   _  | Peter J. Holzer    | Story must make more sense than reality.
|_|_) |                    |
| |   | hjp at hjp.at         |    -- Charles Stross, "Creative writing
__/   | http://www.hjp.at/ |       challenge!"
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