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For loop

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# 1  
Old 05-02-2014
For loop
Code:
a=5


for i in {1..$a}
do 
something
done

it should take 1...5 , when i run above it throwing error , Please help me

---------- Post updated at 03:12 PM ---------- Previous update was at 02:48 PM ----------

I got it

Code:
#!/bin/bash
START=1
END=5
for i in $(eval echo "{$START..$END}")
do
	echo "$i"
done

Last edited by bakunin; 05-02-2014 at 06:03 PM.. Reason: CODE-tags.....
# 2  
Old 05-02-2014
If you ever find yourself using eval, you've taken a wrong turn somewhere. eval is the right answer to forcing {1..$n} to work but you don't need to use that at all.

Code:
for ((X=1; X<=$a; X++))
do
...
done

# 3  
Old 05-02-2014
Quote:
Originally Posted by Corona688
If you ever find yourself using eval, you've taken a wrong turn somewhere.
It is the most efficient method of shooting yourself into everybody elses foot. ;-))

Moderator's Comments:
Mod Comment @Thread-O/P: please use CODE-tags!


bakunin
# 4  
Old 05-02-2014
also ...
Code:
for i in `seq 1 $n`; do echo $i; done

... though you don't need the 1 since you're starting at 1.
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