![](https://secure.gravatar.com/avatar/ecffc5c1eb6692198d091ee98e921822.jpg?s=120&d=mm&r=g)
Dear all, It may be a slight off topic. In the following example, I copied a table “m” to “tempM”, and remove the last row of tempM. Then the output is “ 2, 2” I checked the contents of tempM and m and found that they are same even though I didn’t touch m. I want to remove the last row of tempM while keeping the table m untouched. Please tell me how to do it. Thank you. Best regards, Dalyoung \startbuffer[test] \startluacode m = {{0, 2, 4},{2, 3 , 4}, {2, 2, -6}} local tempM = {} tempM = m table.remove(tempM) context(#tempM, “, ” , #m) \stopluacode \stopbuffer \starttext getbuffer[test] \stoptext
![](https://secure.gravatar.com/avatar/60f3cc97f94fa3690ba406f8c1a7fc4f.jpg?s=120&d=mm&r=g)
On 02/13/2017 06:50 AM, Jeong Dal wrote:
Dear all,
It may be a slight off topic. In the following example, I copied a table “m” to “tempM”, and remove the last row of tempM. Then the output is “ 2, 2” I checked the contents of tempM and m and found that they are same even though I didn’t touch m. I want to remove the last row of tempM while keeping the table m untouched. Please tell me how to do it.
Thank you. Best regards,
Dalyoung
\startbuffer[test] \startluacode m = {{0, 2, 4},{2, 3 , 4}, {2, 2, -6}} local tempM = {}
tempM = m
Do a deep copy tempM = table.copy(m)
table.remove(tempM) context(#tempM, “, ” , #m) \stopluacode \stopbuffer
\starttext getbuffer[test] \stoptext
___________________________________________________________________________________ If your question is of interest to others as well, please add an entry to the Wiki!
maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://context.aanhet.net archive : https://bitbucket.org/phg/context-mirror/commits/ wiki : http://contextgarden.net ___________________________________________________________________________________
![](https://secure.gravatar.com/avatar/49e63acb01f2ca80efce7eed08310ce8.jpg?s=120&d=mm&r=g)
On 2/13/2017 6:50 AM, Jeong Dal wrote:
Dear all,
It may be a slight off topic. In the following example, I copied a table “m” to “tempM”, and remove the last row of tempM. Then the output is “ 2, 2” I checked the contents of tempM and m and found that they are same even though I didn’t touch m. I want to remove the last row of tempM while keeping the table m untouched. Please tell me how to do it.
\startbuffer[test] \startluacode local t1 = {{0, 2, 4},{2, 3 , 4}, {2, 2, -6}} local t2 = t1 -- t2 points to t1 local t3 = table.copy(t1) table.remove(t3) context.tocontext(t1) context.tocontext(t2) context.tocontext(t3) \stopluacode \stopbuffer \starttext \getbuffer[test] \stoptext
Thank you. Best regards,
Dalyoung
\startbuffer[test] \startluacode m = {{0, 2, 4},{2, 3 , 4}, {2, 2, -6}} local tempM = {}
tempM = m table.remove(tempM) context(#tempM, “, ” , #m) \stopluacode \stopbuffer
\starttext getbuffer[test] \stoptext
___________________________________________________________________________________ If your question is of interest to others as well, please add an entry to the Wiki!
maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://context.aanhet.net archive : https://bitbucket.org/phg/context-mirror/commits/ wiki : http://contextgarden.net ___________________________________________________________________________________
-- ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl -----------------------------------------------------------------
![](https://secure.gravatar.com/avatar/d6e7462bd4209f9c4cd08271985a50df.jpg?s=120&d=mm&r=g)
Hello,
tables in Lua are "shared" - there is one copy until you "deep copy" one to another.
Se comments bellow -
On Mon, 13 Feb 2017 06:50:38 +0100, Jeong Dal
Dear all,
It may be a slight off topic. In the following example, I copied a table “m” to “tempM”, and remove the last row of tempM. Then the output is “ 2, 2” I checked the contents of tempM and m and found that they are same even though I didn’t touch m. I want to remove the last row of tempM while keeping the table m untouched. Please tell me how to do it.
Thank you. Best regards,
Dalyoung
\startbuffer[test] \startluacode m = {{0, 2, 4},{2, 3 , 4}, {2, 2, -6}} local tempM = {} -- OK, 'tempM' and 'm' are different tables - try 'print(tempM, m)' - you'll get two addresses
tempM = m -- Now, 'tempM' and 'm' will point to the same table - "the 'm' table" -- The original 'tempM' table will be forgotten and removed during next garbage collection as there is no other reference to it -- ('tempM' starts pointing to 'm', too) table.remove(tempM) -- Will remove from one context(#tempM, “, ” , #m) -- Obviously - both table point to the same object, try again 'print(tempM, m)' \stopluacode \stopbuffer
\starttext getbuffer[test] \stoptext
Best regards, Lukas -- Ing. Lukáš Procházka | mailto:LPr@pontex.cz Pontex s. r. o. | mailto:pontex@pontex.cz | http://www.pontex.cz | IDDS:nrpt3sn Bezová 1658 147 14 Praha 4 Tel: +420 241 096 751 (+420 720 951 172) Fax: +420 244 461 038
participants (4)
-
Hans Hagen
-
Henri Menke
-
Jeong Dal
-
Procházka Lukáš Ing.