Oh I like it. Indexing the loop number from innermost to outermost makes more
sense. The starting implicit index in case of alone continue/break will always
be known (either 1 or zero). Of course it doesn’t make sense to use negative
index for the loop because breaking from the parent loop will break from any
child loop.
> On Dec 4, 2020, at 11:49 AM, Aveheuzed <a.masson...@ntymail.com> wrote:
>
>>
>> Why not start at break 0 not break 1, similar to sequences starting at index
>> 0?
>>
>> Maybe if break alone without integer, it breaks from the loop it is at
>> similar to the behavior we have right now in Python.
>>
>> E.g.,
>>
>> for matrix in matrix_array : # Index 0
>>
>> for x in range(0,10) : # Index 1
>>
>> for y in range(0,10) : # Index 2
>>
>> for z in range(0,10) : # Index 3
>>
>> if matrix[x][y][z] == 0 :
>>
>> print("Found !")
>>
>> continue 3 # which is equivalent to continue/break alone
>>
> Ok, so, that's yet another proposition; what I meant by "the number of loops
> to break" was not to number the loops in a constant way, but rather to
> specify the number of loop-blocks whose flow to break. In other words, my
> version's behavior depends on the "callsite" if you want to target a specific
> line of code.
>
> To me, to "manually" do "break n", you could read the script upwards starting
> at the break's line, and count the number of for/while loops you encounter;
> when your count matches break's parameter, switch back to the standard code
> flow. Your proposal, on the other hand, requires getting back to the start of
> the script and counting loops downwards. That's not how I understand the
> standard break/continue's behavior, tell me if I'm mistaken :-[…
>
> I meant to start numbering at 1, not at 0, also because of the semantics of
> the statement : "break n" would mean "break from n loops", not "break up to
> the n-th nested loop". Therefore, the parameter-less version, "break;", witch
> I always read as "break out of the (innermost) loop" would read "break 1".
> For me, that's not an index after "break", it's a cardinal: we don't break
> "the loop 0", we break "the first loop".
>
> An added benefit from numbering from one would be to allow a "break 0"
> statement with no effect, e.g. for debugging purposes. (I can see other, more
> esoteric uses, too, if arbitrary expressions were allowed, but, hey,
> consenting adults here.)
>
> I have tried to search for examples of numbering from 1 in Python, I'm sure
> there are some, but I can't recall any just now ;-). Anyway, that's not the
> core point of the proposal; I can concede that one.
>
>
>
> One final point : with my way of numbering, the default parameter would
> always be 1 (or 0, whatever), as opposed to your suggestion where you number
> the loops from outermost to innermost. In our example, if I added / removed a
> loop in the block, a bare "continue;" would have its default parameter vary
> implicitly. Therefore, "continue 3", as you put it, would not be equivalent
> to "continue" alone. I don't like that way of doing it : a default parameter
> has always been a known, constant value ! Of course, you could always
> differentiate between "continue" and "continue <n>", saying they are two
> different statements that behave differently, but then I'd rather have them
> named differently…
>
>
>
> Regards,
>
> Alexis
>
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