I'm trying to write a function that rewrites a value according to a user's choice. So far it looks like this:
while [[ $code_id != [1-28] ]]; do
echo "Please select a value..."
echo "1. A"
echo "2. B"
echo "3. C"
echo "4. D"
...
echo "28. Z"
done
echo "INFO: Code is $code_id."
The user should write a chosen number (1-28). But as a result, code returns me, for a choice. I understand what reason in a condition (while... do), but how I should write this for my code to work?
Here is one possible solution which uses infinite loop that is conditionally break inside.
#!/bin/bash
while true
do
read -p "Enter value: " value
if [[ $value =~ ^[0-9]{1,2}$ ]] && ((value <= 28)); then break; fi
does it a number of one or two digits and if true, does it less or equal to 28?
done
echo "The value is: ${value}"
The ranges within the regular expressions doesn't work as these in math. Think about the ranges here as range of sequential characters from the ASCII table. So the character set [1-28] consists of 1, 2 and 8.
Here is another example. The character set [a-dz] includes the characters from the range a-d, these are a, b, c, d, and the character z.
Within the Bash's execute conditional test [[, when the =~ operator is used, the string to the right of the operator is matched as a regular expression.
Looks like you want to use the Bash's select builtin:
select code_id in {A..Z}; do
[[ -z $code_id ]] || break
done
echo "INFO: Code is ${code_id}."
Output:
1) A 3) C 5) E 7) G 9) I 11) K 13) M 15) O 17) Q 19) S 21) U 23) W 25) Y
2) B 4) D 6) F 8) H 10) J 12) L 14) N 16) P 18) R 20) T 22) V 24) X 26) Z
#? 6
INFO: Code is F.
You may want to limit COLUMNS e.g.:
COLUMNS=1
select code_id in {A..Z}; do
[[ -z $code_id ]] || break
done
echo "INFO: Code is ${code_id}."
Output:
1) A
2) B
3) C
4) D
5) E
6) F
7) G
8) H
9) I
10) J
11) K
12) L
13) M
14) N
15) O
16) P
17) Q
18) R
19) S
20) T
21) U
22) V
23) W
24) X
25) Y
26) Z
#? 17
INFO: Code is Q.
The solution is change a condition to while [[ $rep_id -le 0 || $rep_id -ge 13 ]]; do...
