[Python-ideas] Dict joining using + and +=

Raymond Hettinger raymond.hettinger at gmail.com
Tue Mar 5 21:05:52 EST 2019

> On Mar 5, 2019, at 2:13 PM, Greg Ewing <greg.ewing at canterbury.ac.nz> wrote:
> Rhodri James wrote:
>> I have to go and look in the documentation because I expect the union operator to be '+'.
> Anyone raised on Pascal is likely to find + and * more
> natural. Pascal doesn't have bitwise operators, so it
> re-uses + and * for set operations. I like the economy
> of this arrangement -- it's not as if there's any
> other obvious meaning that + and * could have for sets.

The language SETL (the language of sets) also uses + and * for set operations.¹

For us though, the decision to use  | and & are set in stone.  The time for debating the decision was 19 years ago.²


¹ https://www.linuxjournal.com/article/6805
² https://www.python.org/dev/peps/pep-0218/

More information about the Python-ideas mailing list