PYT - How can I subscribe to a topic in the mailing list?

[vanyp]

And h*ow do I set the topic in my messages?*
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PYT - The expressions described in the Python language reference yield only boolean values

[vanyp]

*I am trying to learn Python from the grammar given in the Python 
language reference and I am surprised.*


*Lets start here:*

*"*
*6.3.4. Calls*

A call calls a callable object (e.g., a function 
) with a possibly 
empty series of arguments 
:


*call *::= |primary 
|"(" [|argument_list 
|[","] | |comprehension 
|] ")"
*argument_list *::= |positional_arguments 
|["," |starred_and_keywords 
|]
["," |keywords_arguments 
|]
| |starred_and_keywords 
|["," |keywords_arguments 
|]
| |keywords_arguments 
|

*positional_arguments*::= positional_item ("," positional_item)*
*positional_item *::= |assignment_expression 
|| "*" |expression 
|

*"*

*continued by:*
*"*
*6.12. Assignment expressions*
*assignment_expression*::= [|identifier 
|":="] |expression 
|

*"*

*Now I look at the following productions:*

*"*
*6.13. Conditional expressions*
*conditional_expression*::= |or_test 
|["if" |or_test 
|"else" |expression 
|]
*expression *::= |conditional_expression 
|| |lambda_expr 
|

*"*

*The first or_test is strange, I assume it should be replaced by expression.*

*But even so I think that the only ways out of the recursion are the 
or_test or the lambda_expr.*


*And by the grammar, those evaluate to booleans as follows:*


*"*
*6.14. Lambdas*
*lambda_expr*::= "lambda" [|parameter_list 
|] ":" |expression 
|

*"*

*and I conclude that the only way out of that branch is also or_test.*

*I then look at or_test:*

*"*
*6.11. Boolean operations*
*or_test *::= |and_test 
|| |or_test 
|"or" |and_test 
|
*and_test*::= |not_test 
|| |and_test 
|"and" |not_test 
|
*not_test*::= |comparison 
|| "not" |not_test 
|

*"*

*and the ony way out is comparison, which by the semantics should return 
a boolean.*


*Looking at comparison gives:*

*"*
**6.10. Comparisons**
*comparison *::= |or_expr 
|(|comp_operator 
||or_expr 
|)*

*comp_operator*::= "<" | ">" | "==" | ">=" | "<=" | "!="
| "is" ["not

Re: Aw: PYT - How can I subscribe to a topic in the mailing list?

[vanyp]

The option to filter by topic is offered in the mailing list 
subscription customization page, although no option list is given. 
Topics may have been a project that was never implemented.


Thank you for your help.


Le 19/02/2022 à 21:30, Karsten Hilbert a écrit :

Betreff: PYT - How can I subscribe to a topic in the mailing list?

Mailing lists don't subdivide by topic.

Your mailer may allow you to filter by Subject:.


And h*ow do I set the topic in my messages?*

not applicable

The equivalent would be the Subject: header.

Karsten

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