Bash difference or preferred negation statementbash if statement behaviour questionPreferred way to install bash functions?Is there any major difference when comparing a variable as a string or as an intBash if statement [: missing `]' errorscript for automount, using if statement. cannot got the resultWhy is my elif being treated as an else statement in my bash script?Usage of -n and -z in test built in - Bashbash if statement different behaviourWTH - command not found - if statement - bash scriptDifference between piping and command expansion
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Bash difference or preferred negation statement
bash if statement behaviour questionPreferred way to install bash functions?Is there any major difference when comparing a variable as a string or as an intBash if statement [: missing `]' errorscript for automount, using if statement. cannot got the resultWhy is my elif being treated as an else statement in my bash script?Usage of -n and -z in test built in - Bashbash if statement different behaviourWTH - command not found - if statement - bash scriptDifference between piping and command expansion
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Is there a difference in bash, or a preferred usage of negation of a statement?
if ! [[ -z "$var" ]]; then
do_something
fi
Versus
if [[ ! -z "$var" ]]; then
do_something
fi
bash shell-script test
edited 7 hours ago
Rui F Ribeiro
42.7k1688147
asked 8 hours ago
guillermo chamorroguillermo chamorro
1456
add a comment |
Is there a difference in bash, or a preferred usage of negation of a statement?
if ! [[ -z "$var" ]]; then
do_something
fi
Versus
if [[ ! -z "$var" ]]; then
do_something
fi
bash shell-script test
edited 7 hours ago
Rui F Ribeiro
42.7k1688147
asked 8 hours ago
guillermo chamorroguillermo chamorro
1456
add a comment |
Is there a difference in bash, or a preferred usage of negation of a statement?
if ! [[ -z "$var" ]]; then
do_something
fi
Versus
if [[ ! -z "$var" ]]; then
do_something
fi
bash shell-script test
edited 7 hours ago
Rui F Ribeiro
42.7k1688147
asked 8 hours ago
guillermo chamorroguillermo chamorro
1456
Is there a difference in bash, or a preferred usage of negation of a statement?
if ! [[ -z "$var" ]]; then
do_something
fi
Versus
if [[ ! -z "$var" ]]; then
do_something
fi
bash shell-script test
bash shell-script test
edited 7 hours ago
Rui F Ribeiro
42.7k1688147
asked 8 hours ago
guillermo chamorroguillermo chamorro
1456
edited 7 hours ago
Rui F Ribeiro
42.7k1688147
asked 8 hours ago
guillermo chamorroguillermo chamorro
1456
edited 7 hours ago
Rui F Ribeiro
42.7k1688147
edited 7 hours ago
Rui F Ribeiro
42.7k1688147
edited 7 hours ago
Rui F Ribeiro
42.7k1688147
42.7k1688147
asked 8 hours ago
guillermo chamorroguillermo chamorro
1456
asked 8 hours ago
guillermo chamorroguillermo chamorro
1456
asked 8 hours ago
guillermo chamorroguillermo chamorro
1456
1456
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
! [[ expression ]]
This will be true if the entire test returns false
[[ ! expression ]]
This will be true if the individual expression returns false.
Since the test can be a compound expression this can be very different. For example:
$ [[ ! 0 -eq 1 || 1 -eq 1 ]] && echo yes || echo no
yes
$ ! [[ 0 -eq 1 || 1 -eq 1 ]] && echo yes || echo no
no
Personally I prefer to use the negation inside the test construct where applicable but it's perfectly fine outside depending on your intent.
answered 8 hours ago
Jesse_bJesse_b
16k33978
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
! [[ expression ]]
This will be true if the entire test returns false
[[ ! expression ]]
This will be true if the individual expression returns false.
Since the test can be a compound expression this can be very different. For example:
$ [[ ! 0 -eq 1 || 1 -eq 1 ]] && echo yes || echo no
yes
$ ! [[ 0 -eq 1 || 1 -eq 1 ]] && echo yes || echo no
no
Personally I prefer to use the negation inside the test construct where applicable but it's perfectly fine outside depending on your intent.
answered 8 hours ago
Jesse_bJesse_b
16k33978
add a comment |
! [[ expression ]]
This will be true if the entire test returns false
[[ ! expression ]]
This will be true if the individual expression returns false.
Since the test can be a compound expression this can be very different. For example:
$ [[ ! 0 -eq 1 || 1 -eq 1 ]] && echo yes || echo no
yes
$ ! [[ 0 -eq 1 || 1 -eq 1 ]] && echo yes || echo no
no
Personally I prefer to use the negation inside the test construct where applicable but it's perfectly fine outside depending on your intent.
answered 8 hours ago
Jesse_bJesse_b
16k33978
add a comment |
! [[ expression ]]
This will be true if the entire test returns false
[[ ! expression ]]
This will be true if the individual expression returns false.
Since the test can be a compound expression this can be very different. For example:
$ [[ ! 0 -eq 1 || 1 -eq 1 ]] && echo yes || echo no
yes
$ ! [[ 0 -eq 1 || 1 -eq 1 ]] && echo yes || echo no
no
Personally I prefer to use the negation inside the test construct where applicable but it's perfectly fine outside depending on your intent.
answered 8 hours ago
Jesse_bJesse_b
16k33978
! [[ expression ]]
This will be true if the entire test returns false
[[ ! expression ]]
This will be true if the individual expression returns false.
Since the test can be a compound expression this can be very different. For example:
$ [[ ! 0 -eq 1 || 1 -eq 1 ]] && echo yes || echo no
yes
$ ! [[ 0 -eq 1 || 1 -eq 1 ]] && echo yes || echo no
no
Personally I prefer to use the negation inside the test construct where applicable but it's perfectly fine outside depending on your intent.
answered 8 hours ago
Jesse_bJesse_b
16k33978
edited 8 hours ago
answered 8 hours ago
Jesse_bJesse_b
16k33978
answered 8 hours ago
Jesse_bJesse_b
16k33978
answered 8 hours ago
Jesse_bJesse_b
16k33978
16k33978
add a comment |
add a comment |
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