# Get value from a seq in session? **URL:** \ **Category:** Gatling (Open-Source)\ **Created:** [January 28, 2014, 1:26am UTC](https://community.gatling.io/t/get-value-from-a-seq-in-session/793 "2014-01-28T01:26:27Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![Kan\_Wu](https://avatars.discourse-cdn.com/v4/letter/k/85e7bf/32.png) [@Kan\_Wu](https://community.gatling.io/u/Kan_Wu)\ **Post date:** [January 28, 2014, 1:26am UTC](https://community.gatling.io/t/get-value-from-a-seq-in-session/793/1 "2014-01-28T01:26:27Z")
Hey Stéphane, sorry to bother you again. i may need some tips to make this working. i have two seq lists from previous regex check, list A, list B. then i use foreach to iterate list A, and use counter to identify the same index element in list B. here is the code: foreach("${ListA}",“A”,“counter”) { exec( http(“Get”) .get("/") .queryParam(""“A”"", “”"${A}""") .queryParam(""“B”"", session =\> session(“ListB”)[session(“counter”).as[Int]]) .pause(0 milliseconds, Properties.requestSleep milliseconds) but the compile didnt pass, 3 errors are all about the format of the brackets. i checked in sessions that both lists are complete and correct. Thanks! ---
**Author:** ![Excilys](https://avatars.discourse-cdn.com/v4/letter/e/8797f3/32.png) [@Excilys](https://community.gatling.io/u/Excilys)\ **Post date:** [January 28, 2014, 8:50am UTC](https://community.gatling.io/t/get-value-from-a-seq-in-session/793/2 "2014-01-28T08:50:48Z")
With as: .queryParam(""“B”"", session =\> { val listB = session(“ListB”).as[Seq[String]] val counter = session(“counter”).as[Int] listB(counter) }) With validate (safer): .queryParam(""“B”"", session =\> for { listB ← session(“ListB”).validate[Seq[String]] counter ← session(“counter”).validate[Int] } yield listB(counter) ) ---
**Author:** ![Kan\_Wu](https://avatars.discourse-cdn.com/v4/letter/k/85e7bf/32.png) [@Kan\_Wu](https://community.gatling.io/u/Kan_Wu)\ **Post date:** [January 28, 2014, 5:51pm UTC](https://community.gatling.io/t/get-value-from-a-seq-in-session/793/3 "2014-01-28T17:51:07Z")
Works perfectly in gatling 2, thanks a lot!! 在 2014年1月28日星期二UTC-8上午12时50分48秒，Stéphane Landelle写道： ---
**Author:** ![Kan\_Wu](https://avatars.discourse-cdn.com/v4/letter/k/85e7bf/32.png) [@Kan\_Wu](https://community.gatling.io/u/Kan_Wu)\ **Post date:** [January 28, 2014, 7:29pm UTC](https://community.gatling.io/t/get-value-from-a-seq-in-session/793/4 "2014-01-28T19:29:54Z")
is is possible to re-use listB in next exec? for example, i dont want use counter anymore, but a random value. .queryParam(""“weight”"", session =\> { val listB = session(“ListB”).as[Seq[String]] val random = getRand(listB.size) listB(random) }) in next exec, i want to re-use the random value and listB if possible, how can i do this? compilation said value listB, random not found. 在 2014年1月28日星期二UTC-8上午12时50分48秒，Stéphane Landelle写道： ---
**Author:** ![Kan\_Wu](https://avatars.discourse-cdn.com/v4/letter/k/85e7bf/32.png) [@Kan\_Wu](https://community.gatling.io/u/Kan_Wu)\ **Post date:** [January 28, 2014, 8:36pm UTC](https://community.gatling.io/t/get-value-from-a-seq-in-session/793/5 "2014-01-28T20:36:03Z")
i think i can use session set attribute to set the random. 在 2014年1月28日星期二UTC-8上午11时29分54秒，Kan Wu写道： ---
**Author:** ![Excilys](https://avatars.discourse-cdn.com/v4/letter/e/8797f3/32.png) [@Excilys](https://community.gatling.io/u/Excilys)\ **Post date:** [January 28, 2014, 9:55pm UTC](https://community.gatling.io/t/get-value-from-a-seq-in-session/793/6 "2014-01-28T21:55:09Z")
I feel stupid: I totally forgot that Gatling EL supports this out of the box! “${ListB(counter)}” “${ListB.random}” ---
**Author:** ![Kan\_Wu](https://avatars.discourse-cdn.com/v4/letter/k/85e7bf/32.png) [@Kan\_Wu](https://community.gatling.io/u/Kan_Wu)\ **Post date:** [January 28, 2014, 11:54pm UTC](https://community.gatling.io/t/get-value-from-a-seq-in-session/793/7 "2014-01-28T23:54:23Z")
nice. but if i want function like indexOf, i have to save that the seq to a list first? That’s what i’m doing now and it works fine. 在 2014年1月28日星期二UTC-8下午1时55分09秒，Stéphane Landelle写道： ---
**Author:** ![Excilys](https://avatars.discourse-cdn.com/v4/letter/e/8797f3/32.png) [@Excilys](https://community.gatling.io/u/Excilys)\ **Post date:** [January 29, 2014, 8:12am UTC](https://community.gatling.io/t/get-value-from-a-seq-in-session/793/8 "2014-01-29T08:12:24Z")
Sorry, I don’t get it. indexOf is defined on Seq (which is a trait that List extends). ---
**Author:** ![Kan\_Wu](https://avatars.discourse-cdn.com/v4/letter/k/85e7bf/32.png) [@Kan\_Wu](https://community.gatling.io/u/Kan_Wu)\ **Post date:** [January 29, 2014, 5:41pm UTC](https://community.gatling.io/t/get-value-from-a-seq-in-session/793/9 "2014-01-29T17:41:52Z")
sorry. i didnt say it clearly. this is my code of how doing it: exec(session =\> { val tList = session(“typeList”).as[Seq[String]] val wList = session(“weightList”).as[Seq[String]] val index = tList.indexOf(“0”) val weight = wList(index) session.set(“index”,index) session.set(“weight”,weight) }) we can simply use ${typeList.indexOf(“0”)} and skip saving to a local val first? 在 2014年1月29日星期三UTC-8上午12时12分24秒，Stéphane Landelle写道： ---
**Author:** ![Excilys](https://avatars.discourse-cdn.com/v4/letter/e/8797f3/32.png) [@Excilys](https://community.gatling.io/u/Excilys)\ **Post date:** [January 29, 2014, 5:44pm UTC](https://community.gatling.io/t/get-value-from-a-seq-in-session/793/10 "2014-01-29T17:44:16Z")
indexOf isn’t supported in Gatling EL. Gatling EL is meant to be very simple and not a full blown kind of dynamic language inside Scala code. ---
**Author:** ![Excilys](https://avatars.discourse-cdn.com/v4/letter/e/8797f3/32.png) [@Excilys](https://community.gatling.io/u/Excilys)\ **Post date:** [January 29, 2014, 5:45pm UTC](https://community.gatling.io/t/get-value-from-a-seq-in-session/793/11 "2014-01-29T17:45:54Z")
Where does this “0” attribute come from? ---
**Author:** ![Kan\_Wu](https://avatars.discourse-cdn.com/v4/letter/k/85e7bf/32.png) [@Kan\_Wu](https://community.gatling.io/u/Kan_Wu)\ **Post date:** [January 29, 2014, 5:46pm UTC](https://community.gatling.io/t/get-value-from-a-seq-in-session/793/12 "2014-01-29T17:46:52Z")
this is what i expected too. my code is working fine. Thanks a lot for your response! btw, i sent you an email in detail of the issue we talked about. 在 2014年1月29日星期三UTC-8上午9时44分16秒，Stéphane Landelle写道： ---
**Author:** ![Kan\_Wu](https://avatars.discourse-cdn.com/v4/letter/k/85e7bf/32.png) [@Kan\_Wu](https://community.gatling.io/u/Kan_Wu)\ **Post date:** [January 29, 2014, 5:49pm UTC](https://community.gatling.io/t/get-value-from-a-seq-in-session/793/13 "2014-01-29T17:49:23Z")
“0” is a value of the seq. i want to know the index of “0” in tList, then get the same index element from list wList. 在 2014年1月29日星期三UTC-8上午9时45分54秒，Stéphane Landelle写道： ---
**Author:** ![Excilys](https://avatars.discourse-cdn.com/v4/letter/e/8797f3/32.png) [@Excilys](https://community.gatling.io/u/Excilys)\ **Post date:** [January 29, 2014, 9:07pm UTC](https://community.gatling.io/t/get-value-from-a-seq-in-session/793/14 "2014-01-29T21:07:22Z")
If tList and wList are supposed to work together, I guess I’d first zip them together (so I’d get a Seq[(String, String)]), loop over the result and add a exec(function) that would expose the Tuple2 current element into 2 dedicated attributes. Get it? ---
**Author:** ![Kan\_Wu](https://avatars.discourse-cdn.com/v4/letter/k/85e7bf/32.png) [@Kan\_Wu](https://community.gatling.io/u/Kan_Wu)\ **Post date:** [January 29, 2014, 11:06pm UTC](https://community.gatling.io/t/get-value-from-a-seq-in-session/793/15 "2014-01-29T23:06:02Z")
yes. i see your point here but we use two lists in separate places but only need to get the index value. i will try your suggestion if it could life efficiency. Thanks for helping out! 在 2014年1月29日星期三UTC-8下午1时07分22秒，Stéphane Landelle写道：