linux shell array create difference using between parentheses and declare
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0
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In a Linux shell, there are two ways to create an array.
- declare -a array
- array=()
but when I check if an array is empty using
if [ ${#array[@]} -eq 0 ]
when an array is created using the declare -a array.it will have an error "unbound variabl".however, it works fine when using array=()
linux shell-script bash-array
edited Dec 6 at 6:28
msp9011
3,65543863
asked Dec 6 at 6:22
focus zheng
14
add a comment |
up vote
0
down vote
favorite
In a Linux shell, there are two ways to create an array.
- declare -a array
- array=()
but when I check if an array is empty using
if [ ${#array[@]} -eq 0 ]
when an array is created using the declare -a array.it will have an error "unbound variabl".however, it works fine when using array=()
linux shell-script bash-array
edited Dec 6 at 6:28
msp9011
3,65543863
asked Dec 6 at 6:22
focus zheng
14
for me, both options works!!
– msp9011
Dec 6 at 6:36
what is your bash version?when >=4.4,both is working.
– focus zheng
Dec 6 at 11:09
add a comment |
up vote
0
down vote
favorite
up vote
0
down vote
favorite
In a Linux shell, there are two ways to create an array.
- declare -a array
- array=()
but when I check if an array is empty using
if [ ${#array[@]} -eq 0 ]
when an array is created using the declare -a array.it will have an error "unbound variabl".however, it works fine when using array=()
linux shell-script bash-array
edited Dec 6 at 6:28
msp9011
3,65543863
asked Dec 6 at 6:22
focus zheng
14
In a Linux shell, there are two ways to create an array.
- declare -a array
- array=()
but when I check if an array is empty using
if [ ${#array[@]} -eq 0 ]
when an array is created using the declare -a array.it will have an error "unbound variabl".however, it works fine when using array=()
linux shell-script bash-array
linux shell-script bash-array
edited Dec 6 at 6:28
msp9011
3,65543863
asked Dec 6 at 6:22
focus zheng
14
edited Dec 6 at 6:28
msp9011
3,65543863
asked Dec 6 at 6:22
focus zheng
14
edited Dec 6 at 6:28
msp9011
3,65543863
edited Dec 6 at 6:28
msp9011
3,65543863
edited Dec 6 at 6:28
msp9011
3,65543863
3,65543863
asked Dec 6 at 6:22
focus zheng
14
asked Dec 6 at 6:22
focus zheng
14
asked Dec 6 at 6:22
focus zheng
14
14
for me, both options works!!
– msp9011
Dec 6 at 6:36
what is your bash version?when >=4.4,both is working.
– focus zheng
Dec 6 at 11:09
add a comment |
for me, both options works!!
– msp9011
Dec 6 at 6:36
what is your bash version?when >=4.4,both is working.
– focus zheng
Dec 6 at 11:09
for me, both options works!!
– msp9011
Dec 6 at 6:36
for me, both options works!!
– msp9011
Dec 6 at 6:36
what is your bash version?when >=4.4,both is working.
– focus zheng
Dec 6 at 11:09
what is your bash version?when >=4.4,both is working.
– focus zheng
Dec 6 at 11:09
add a comment |
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for me, both options works!!
– msp9011
Dec 6 at 6:36
what is your bash version?when >=4.4,both is working.
– focus zheng
Dec 6 at 11:09