Thanks for the suggestion, Richard.

The only downside to that is that your 'Subject:' line now has least three identifiers: the list-id, the admin-id, and the topic-id.

    Subject: [FlyGuys] [Admin] [B-26] Re: cockpit vent repair

I was hoping to avoid the Subject bloat, and it crossed my mind that the list-id itself could be considered the common "topic".  I wasn't sure if the string "[FlyGuys]" in the Subject would be recognized as a "topic", or if it would be ignored because it was the list-id.  Or if it mattered, since its primary purpose is to enable the "no-match filter" option in the first place.

Any insights would be appreciated.

Question 2: If a 'Subject:' line has multiple topic-ids, will a copy of the posting will be sent to the union set of members of the topics?  IOW, if a member is subscribed to those topics will he get multiple copies in that case?

Question 3: What effect do Topics have on subscribers receiving the Digest?  Are they effectively subscribed to all Topics?

I see great potential for the use of Topics in our group, but I don't know where to find the answers besides here.

Thanks!

-Chip-

On 10/13/2020 3:57 PM, Richard Damon wrote:

I create one topic that I request everyone using topic to select for important administrative messages from the moderator of the list. That gives them something to select if they don't want any of the normal topics.

On 10/13/20 3:21 PM, Chip Davis wrote:

...

I'm trying to set up Topics for a Mailman 2.1.33 list I administer, and I'm a tad confused.

There appears to be no combination of options to allow a member of a list to see _only_ non-topic-specific postings.

If you select one or more topics of interest, you will receive the postings under those topics.  You will not receive any _topic-specific_ postings that do not match your selections. Furthermore, if you have also set "Do you want to receive messages that do not match any topic filter?" to 'Yes', you will also receive all messages that are _not_ associated with a topic.  Otherwise, you will receive _only_ the postings associated with your selected topics.  (This appears to function as expected.)

However, if you have not selected any topics, you will receive all postings, whether topic-specific or not, regardless the setting of "Do you want to receive messages that do not match any topic filter?".

I would like to offer the members of my lists the option of receiving: 1. All of the postings to the list [All topic categories selected + no-match filter=Yes] 2. Specific topics and all non-topic postings [At least one topic category selected + no-match filter=Yes] 3. Specific topics only [At least one topic category selected + no-match filter=No] 4. Only _non-topic_ postings [No topic categories selected + no-match filter=No]

Apparently that is not the heuristic being applied.  If no topic categories are selected, the no-match filter setting is ignored (i.e. defaults to 'Yes') effectively delivering all listserver traffic to that user, and eliminating option 4.  This is "as documented" and embarrassingly empirically demonstrated.  :-/

There seems to be no obvious way to say "I want to see only those postings that are not topic-specific".

If I put the list's subject_prefix in as the Topic1 regexp (escaped as necessary), would the member be able to select it and specify 'no-match filter=No' to receive _only_ the non-topic-specific postings?  (I would test this question myself, but see "embarrassingly empirically demonstrated", above.)

If this question has already been addressed in a document somewhere, please point me to it.

Thanks!

-Chip-

Thank you, Gentlemen!

That was quite enlightening and _very_ helpful.

I'm very grateful for your extensive explanations and examples and am going to give Topics a try and see if the subscribers take to them.

-Chip-

On 10/13/2020 5:51 PM, Mark Sapiro wrote:

On 10/13/20 1:56 PM, Chip Davis wrote:

...

Thanks for the suggestion, Richard.

The only downside to that is that your 'Subject:' line now has least three identifiers: the list-id, the admin-id, and the topic-id.

    Subject: [FlyGuys] [Admin] [B-26] Re: cockpit vent repair

I was hoping to avoid the Subject bloat, and it crossed my mind that the list-id itself could be considered the common "topic".  I wasn't sure if the string "[FlyGuys]" in the Subject would be recognized as a "topic", or if it would be ignored because it was the list-id.  Or if it mattered, since its primary purpose is to enable the "no-match filter" option in the first place.

As noted in another reply, matching on subject_prefix won't work.

Also, I don't understand 'subject bloat'

Consider defining a topic named Get_only_nonmatchind with a regexp ov say

^This_is_a_bogus_topic_that_I_hope_will_never_match_a_real_message_ig35yth3hg3ot4ohj430$

And a description of say

Subscribe to this topic and enable receiving messages that don't match any topic to receive only messages that don't match any other topic.

...

Any insights would be appreciated.

Question 2: If a 'Subject:' line has multiple topic-ids, will a copy of the posting will be sent to the union set of members of the topics? Short answer - Yes

What you call multiple topic IDs are actually just things that match a topic regexp.

For example, if topic1 has regexp \WMailman\W and topic2 has regexp \Wlist\W, any message containing a Subject: or Topics: header or pseudo header containing the word Mailman (matched case insensitively) will be delivered to every regular member subscribed to topic1 plus those subscribed to no topics. Any message containing a Subject: or Topics: header or pseudo header containing the word list (matched case insensitively) will be delivered to every regular member subscribed to topic2 plus those subscribed to no topics. Any message containing a Subject: or Topics: header or pseudo header containing both the words Mailman and list (matched case insensitively) will be delivered to every regular member subscribed to topic1 plus those subscribed to topic2 plus those subscribed to no topics.

...

IOW, if a member is subscribed to those topics will he get multiple copies in that case? No.

...

Question 3: What effect do Topics have on subscribers receiving the Digest?  Are they effectively subscribed to all Topics?

Digests contain all messages without any regard to topics.

...

I see great potential for the use of Topics in our group, but I don't know where to find the answers besides here.

On 10/15/20 1:41 PM, Grant Taylor via Mailman-Users wrote:

On 10/13/20 3:51 PM, Mark Sapiro wrote:

...

For example, if topic1 has regexp \WMailman\W and topic2 has regexp \Wlist\W, any message containing a Subject: or Topics: header or pseudo header containing the word Mailman ...

What is a "pseudo header" in this context?

Are you referring to the first line of the message body being abused and treated like a header?

Not exactly. In order to support MUAs that make it difficult to add a custom header such as Keywords: There is a topics_bodylines_limit setting, described as:

topics_bodylines_limit (topics): How many body lines should the topic matcher scan?

The topic matcher will scan this many lines of the message body looking for topic keyword matches. Body scanning stops when either this many lines have been looked at, or a non-header-like body line is encountered. By setting this value to zero, no body lines will be scanned (i.e. only the Keywords: and Subject: headers will be scanned). By setting this value to a negative number, then all body lines will be scanned until a non-header-like line is encountered.

In another post in this thread, I referred to a Topics: header, I meant Keywords:, not Topics. As far as searching the message body for what I referred to as pseudo-headers it will only look at an outer text/plain part or a text/plain part within an outer multipart/alternative part, and it will look at any lines up to topics_bodylines_limit or the first non-header like line for Subject: or Keywords: matches.

-- Mark Sapiro <mark@msapiro.net> The highway is for gamblers, San Francisco Bay Area, California better use your sense - B. Dylan

Thanks for the suggestion, Richard.

The only downside to that is that your 'Subject:' line now has least three identifiers: the list-id, the admin-id, and the topic-id.

    Subject: [FlyGuys] [Admin] [B-26] Re: cockpit vent repair

I was hoping to avoid the Subject bloat, and it crossed my mind that the list-id itself could be considered the common "topic".  I wasn't sure if the string "[FlyGuys]" in the Subject would be recognized as a "topic", or if it would be ignored because it was the list-id.  Or if it mattered, since its primary purpose is to enable the "no-match filter" option in the first place.

Any insights would be appreciated.

Question 2: If a 'Subject:' line has multiple topic-ids, will a copy of the posting will be sent to the union set of members of the topics?  IOW, if a member is subscribed to those topics will he get multiple copies in that case?

Question 3: What effect do Topics have on subscribers receiving the Digest?  Are they effectively subscribed to all Topics?

I see great potential for the use of Topics in our group, but I don't know where to find the answers besides here.

Thanks!

-Chip-

On 10/13/2020 3:57 PM, Richard Damon wrote:

I create one topic that I request everyone using topic to select for important administrative messages from the moderator of the list. That gives them something to select if they don't want any of the normal topics.

On 10/13/20 3:21 PM, Chip Davis wrote:

...

I'm trying to set up Topics for a Mailman 2.1.33 list I administer, and I'm a tad confused.

There appears to be no combination of options to allow a member of a list to see _only_ non-topic-specific postings.

If you select one or more topics of interest, you will receive the postings under those topics.  You will not receive any _topic-specific_ postings that do not match your selections. Furthermore, if you have also set "Do you want to receive messages that do not match any topic filter?" to 'Yes', you will also receive all messages that are _not_ associated with a topic.  Otherwise, you will receive _only_ the postings associated with your selected topics.  (This appears to function as expected.)

However, if you have not selected any topics, you will receive all postings, whether topic-specific or not, regardless the setting of "Do you want to receive messages that do not match any topic filter?".

I would like to offer the members of my lists the option of receiving: 1. All of the postings to the list [All topic categories selected + no-match filter=Yes] 2. Specific topics and all non-topic postings [At least one topic category selected + no-match filter=Yes] 3. Specific topics only [At least one topic category selected + no-match filter=No] 4. Only _non-topic_ postings [No topic categories selected + no-match filter=No]

Apparently that is not the heuristic being applied.  If no topic categories are selected, the no-match filter setting is ignored (i.e. defaults to 'Yes') effectively delivering all listserver traffic to that user, and eliminating option 4.  This is "as documented" and embarrassingly empirically demonstrated.  :-/

There seems to be no obvious way to say "I want to see only those postings that are not topic-specific".

If I put the list's subject_prefix in as the Topic1 regexp (escaped as necessary), would the member be able to select it and specify 'no-match filter=No' to receive _only_ the non-topic-specific postings?  (I would test this question myself, but see "embarrassingly empirically demonstrated", above.)

If this question has already been addressed in a document somewhere, please point me to it.

Thanks!

-Chip-

Thank you, Gentlemen!

That was quite enlightening and _very_ helpful.

I'm very grateful for your extensive explanations and examples and am going to give Topics a try and see if the subscribers take to them.

-Chip-

On 10/13/2020 5:51 PM, Mark Sapiro wrote:

On 10/13/20 1:56 PM, Chip Davis wrote:

...

Thanks for the suggestion, Richard.

The only downside to that is that your 'Subject:' line now has least three identifiers: the list-id, the admin-id, and the topic-id.

    Subject: [FlyGuys] [Admin] [B-26] Re: cockpit vent repair

I was hoping to avoid the Subject bloat, and it crossed my mind that the list-id itself could be considered the common "topic".  I wasn't sure if the string "[FlyGuys]" in the Subject would be recognized as a "topic", or if it would be ignored because it was the list-id.  Or if it mattered, since its primary purpose is to enable the "no-match filter" option in the first place.

As noted in another reply, matching on subject_prefix won't work.

Also, I don't understand 'subject bloat'

Consider defining a topic named Get_only_nonmatchind with a regexp ov say

^This_is_a_bogus_topic_that_I_hope_will_never_match_a_real_message_ig35yth3hg3ot4ohj430$

And a description of say

Subscribe to this topic and enable receiving messages that don't match any topic to receive only messages that don't match any other topic.

...

Any insights would be appreciated.

Question 2: If a 'Subject:' line has multiple topic-ids, will a copy of the posting will be sent to the union set of members of the topics? Short answer - Yes

What you call multiple topic IDs are actually just things that match a topic regexp.

For example, if topic1 has regexp \WMailman\W and topic2 has regexp \Wlist\W, any message containing a Subject: or Topics: header or pseudo header containing the word Mailman (matched case insensitively) will be delivered to every regular member subscribed to topic1 plus those subscribed to no topics. Any message containing a Subject: or Topics: header or pseudo header containing the word list (matched case insensitively) will be delivered to every regular member subscribed to topic2 plus those subscribed to no topics. Any message containing a Subject: or Topics: header or pseudo header containing both the words Mailman and list (matched case insensitively) will be delivered to every regular member subscribed to topic1 plus those subscribed to topic2 plus those subscribed to no topics.

...

IOW, if a member is subscribed to those topics will he get multiple copies in that case? No.

...

Question 3: What effect do Topics have on subscribers receiving the Digest?  Are they effectively subscribed to all Topics?

Digests contain all messages without any regard to topics.

...

I see great potential for the use of Topics in our group, but I don't know where to find the answers besides here.

On 10/15/20 1:41 PM, Grant Taylor via Mailman-Users wrote:

On 10/13/20 3:51 PM, Mark Sapiro wrote:

...

For example, if topic1 has regexp \WMailman\W and topic2 has regexp \Wlist\W, any message containing a Subject: or Topics: header or pseudo header containing the word Mailman ...

What is a "pseudo header" in this context?

Are you referring to the first line of the message body being abused and treated like a header?

Not exactly. In order to support MUAs that make it difficult to add a custom header such as Keywords: There is a topics_bodylines_limit setting, described as:

topics_bodylines_limit (topics): How many body lines should the topic matcher scan?

The topic matcher will scan this many lines of the message body looking for topic keyword matches. Body scanning stops when either this many lines have been looked at, or a non-header-like body line is encountered. By setting this value to zero, no body lines will be scanned (i.e. only the Keywords: and Subject: headers will be scanned). By setting this value to a negative number, then all body lines will be scanned until a non-header-like line is encountered.

In another post in this thread, I referred to a Topics: header, I meant Keywords:, not Topics. As far as searching the message body for what I referred to as pseudo-headers it will only look at an outer text/plain part or a text/plain part within an outer multipart/alternative part, and it will look at any lines up to topics_bodylines_limit or the first non-header like line for Subject: or Keywords: matches.

-- Mark Sapiro <mark@msapiro.net> The highway is for gamblers, San Francisco Bay Area, California better use your sense - B. Dylan