Anyone used github.com/orcaman/concurrent-map? Is is it a good package?

oh, no I don't expose it. but I embed mutex like: type JoeBidenIsNotPresident { sync.Mutex val int } func(JBINP ...) Add() { JBINP.Lock() JBINP.val++ JBINP.Unlock() } ohhh, I guess this exposes mutex as well?

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23.11.2020

Roman Sharkov

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oh, no I don't expose it. but I embed mutex like: ...

you do expose it, that’s what embedding does

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23.11.2020

Roman Sharkov

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oh, no I don't expose it. but I embed mutex like: ...

also, use defer Unlock(), there’s no more additional runtime cost for those kinds of defers since 1.14

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23.11.2020

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Roman Sharkov
also, use defer Unlock(), there’s no more addition...

I've just read an old article

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23.11.2020

Mark X

What about sync.Map? What’s missing there for you?

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23.11.2020

Mark X

Mark X
What about sync.Map? What’s missing there for you?

https://golang.org/pkg/sync/#Map

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23.11.2020

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Mark X
What about sync.Map? What’s missing there for you?

I don't know lol, actually I haven't really studied all aspects of mutexes. Let me see that

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23.11.2020

Roman Sharkov

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I don't know lol, actually I haven't really studie...

just use sync.Map if you don’t know why you’d need something else

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23.11.2020

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Roman Sharkov
just use sync.Map if you don’t know why you’d need...

I'm using it to control conversations so functions in the app don't call db independently and use an interface to interact with conversations table

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23.11.2020

Roman Sharkov

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I'm using it to control conversations so functions...

I don’t understand 🙂

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23.11.2020

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Roman Sharkov
I don’t understand 🙂

Conversation table in db has a few fields like last_message_Id. If 2 users in a conversation call that record at the same time and increment last_message_id, then both might get same message ids.

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23.11.2020

Roman Sharkov

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Conversation table in db has a few fields like las...

you’re supposed to use transactions for these kinds of problems

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23.11.2020

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Roman Sharkov
you’re supposed to use transactions for these kind...

I'm not sure if transactions would help here. last_message_id = 0 User A sends a new message to User B User B sends a new message to User A Both at the same time, now the updates handler goroutine fetch last_message_id for each request, both will fetch 0 in this case. So if they try to update the value, it will be 1 instead of 2. I thought transactions is only when you want to write data

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23.11.2020

Roman Sharkov

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I'm not sure if transactions would help here. la...

that’s exactly what transactions were made for

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23.11.2020

Roman Sharkov

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I'm not sure if transactions would help here. la...

> I thought transactions is only when you want to write data no.

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23.11.2020