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Ok, now I'm mildly curious to knpw:

What is the justification for causing list == 3 to evaluate to False, besides the obvious "a list cannot equal a number"?

On Tue, May 28, 2019 at 7:52 PM Rob Cliffe <rob.cliffe@btinternet.com> wrote:

On 27/05/2019 04:52:17, Montana Burr wrote:
\> NumPy arrays have this awesome feature, where array == 3 does an
\> element-wise comparison and returns a list. For example:
\>
\> np.array(\[1,2,3,4,5\])==3
\>
\> returns
\>
\> \[False,False,True,False,False\]
\>
\> It would be cool if Python had similar functionality for lists.
\>
Well, it does have:
\>>> \[x==3 for x in \[1,2,3,4,5\]\]
\[False, False, True, False, False\]

This is IMHO much more intuitive than your construct overloading "==".
It is also more flexible (any operation can be performed on x, not just
an equality comparison).
So sorry, but I can see no justification for changing the Python
language to do something, which can already be done, to be done in a
more obscure way.
Also
\[1,2,3,4,5\]==3
is already legal syntax (it evaluates to False, since the operands are
not equal), so you are proposing a code-breaking change.

Apologies if someone has already pointed all this out, as is very likely
(I have only just (re-)joined python-ideas and may have missed the
relevant posts).
Best wishes
Rob Cliffe

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