[SOLVED]: Is "2nd level indirection" possible in bash?

[Walter Dnes]

  I finally figured out a compromise that does not use eval.  I want
to stay away from eval.  I was trying to bite off too much in one step...

* This does *NOT* work without eval
dataline="2432187.20,  1248.2754,  1947,  01,  01,     .0,     .0,     .0"
f_yr="25:4"
yyyy="\${dataline:${f_yr}}"

* This does work without eval
dataline="2432187.20,  1248.2754,  1947,  01,  01,     .0,     .0,     .0"
f_yr_start=25
f_yr_len=4
yyyy="${dataline:${f_yr_start}:${f_yr_len}}"
echo "${yyyy}"

  The key is to substitute an integer separately for the start and
length parameters, rather than trying to write the entire expression to
be evaluated.

-- 
Walter Dnes <waltdnes-SLHPyeZ9y/tg9hUCZPvPmw at public.gmane.org>
I don't run "desktop environments"; I run useful applications
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