As I had to think about it a few minutes, I thought I should share the
solution.
In the original program I was building a table from three separate
files, for which
records with all the same keys do not exist. But I know, now, what to do.
---------------------------------------------------------------------------------------------------------------
record health_row(yr,mo,wgt)
procedure main()
null_master := health_row(-1,-1,-1)
write("Hello World")
master_tbl := table()
mo := "01"
yr := "2014"
glu_key := "DT" || yr || "/" || mo
wgt := 198
write("glu key = ",glu_key," wgt = ", wgt)
master_tbl[glu_key] := health_row(yr,mo,wgt)
mo := "02"
yr := "2014"
glu_key := "DT" || yr || "/" || mo
wgt := 196
write("glu key = ",glu_key," wgt = ", wgt)
master_tbl[glu_key] := health_row(yr,mo,wgt)
mo := "01"
yr := "2014"
glu_key := "DT" || yr || "/" || mo
write("glu key = ",glu_key," wgt = from table ",
master_tbl[glu_key].wgt)
write("Now You get correct value!")
end
---------------------------------------------------------------------------------------------------------------------
Hello World
glu key = DT2014/01 wgt = 198
glu key = DT2014/02 wgt = 196
glu key = DT2014/01 wgt = from table 198
Now You get correct value!
----------------------------------------------------------------------------------------------------------------------
Dennis Darland
stud...@dennisdarland.com
On 3/1/2014 1:17 AM, Jeffery, Clint (jeffe...@uidaho.edu) wrote:
> Icon (and Unicon, due to obsessive backward compatibility) do not create a
> separate copy of the table default value each time the table is subscripted
> with a non-existent key. Instead they produce a reference to the (singleton)
> default value. When you are using this default value in order to "insert"
> elements into the table, you are really just inserting multiple keys that are
> sharing the same health_row instance. The workaround is pretty easy -- but we
> might have a lively discussion of whether this is one of the <1% of the cases
> where we should break backward compatibility, since it is a fairly common
> source of bugs and arguable would be more useful if it was modified to
> copy-on-insert.
> ________________________________________
> From: Dennis Darland - student <stud...@dennisdarland.com>
> Subject: [Unicon-group] What am I doing wrong - table of records
>
> I've mostly been using Ruby lately, but I like to use different languages.
> I was writing a much larger program, and kept having troubles.
> I simplified it to this sample program. (really just Icon.)
> It happens with both linux and windows.
> ---------------------------------------------------------------------------------------------------------------
>
>
> record health_row(yr,mo,wgt)
>
> procedure main()
> null_master := health_row(-1,-1,-1)
> write("Hello World")
> master_tbl := table(null_master)
> mo := "01"
> yr := "2014"
>
> glu_key := "DT" || yr || "/" || mo
> wgt := 198
> write("glu key = ",glu_key," wgt = ", wgt)
> master_tbl[glu_key].yr := yr
> master_tbl[glu_key].mo := mo
> master_tbl[glu_key].wgt := wgt
>
> mo := "02"
> yr := "2014"
> glu_key := "DT" || yr || "/" || mo
> wgt := 196
> write("glu key = ",glu_key," wgt = ", wgt)
> master_tbl[glu_key].yr := yr
> master_tbl[glu_key].mo := mo
> master_tbl[glu_key].wgt := wgt
>
> mo := "01"
> yr := "2014"
>
> glu_key := "DT" || yr || "/" || mo
> write("glu key = ",glu_key," wgt = from table ",
> master_tbl[glu_key].wgt)
> write("You get last value - why not from table?")
> end
> ----------------------------------------------------------------------------------------------------------------------
> Hello World
> glu key = DT2014/01 wgt = 198
> glu key = DT2014/02 wgt = 196
> glu key = DT2014/01 wgt = from table 196
> You get last value - why not from table?
> ----------------------------------------------------------------------------------------------------------------------
>
>
>
>
>
> --
> Dennis Darland
> stud...@dennisdarland.com
>
>
> ------------------------------------------------------------------------------
> Flow-based real-time traffic analytics software. Cisco certified tool.
> Monitor traffic, SLAs, QoS, Medianet, WAAS etc. with NetFlow Analyzer
> Customize your own dashboards, set traffic alerts and generate reports.
> Network behavioral analysis & security monitoring. All-in-one tool.
> http://pubads.g.doubleclick.net/gampad/clk?id=126839071&iu=/4140/ostg.clktrk
> _______________________________________________
> Unicon-group mailing list
> Unicon-group@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/unicon-group
------------------------------------------------------------------------------
Flow-based real-time traffic analytics software. Cisco certified tool.
Monitor traffic, SLAs, QoS, Medianet, WAAS etc. with NetFlow Analyzer
Customize your own dashboards, set traffic alerts and generate reports.
Network behavioral analysis & security monitoring. All-in-one tool.
http://pubads.g.doubleclick.net/gampad/clk?id=126839071&iu=/4140/ostg.clktrk
_______________________________________________
Unicon-group mailing list
Unicon-group@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/unicon-group
