Varibles - Union [duplicate]

Question

FICH10=primero.sh
FICH20=segundo.sh

for i in 10 20
do
   echo $FICH($i)  # I want resolved first $i and then resolver var FICH10
done

I want it to first solve $i and concatenate it to the FICH shoreline and thus return the value of $FICH10 or $FICH20 but without having to put the numbers, but they are resolved by the loop

I don't solved with the response asocciate

$ for i in 10 20
> do
> echo $((FICH$i))
> done
ksh: line 3: primero: parameter not set

Answer 1

Use variable indirection:

#!/bin/bash
fich10=primero.sh
fich20=segundo.sh

for i in 10 20 ; do
    var=fich$i
    echo ${!var}
done

Note I used small caps for variable names as they aren't system variables.

Answer 2

With bash versions 4.3+, you can use a "nameref":

for i in 10 20; do
    declare -n var="FICH$i"
    echo "$var"
done

---

We can use eval to force a second round of variable substitutions, but as you can see, that's not required. eval is generally considered too dangerous to use for most cases.