3 SC2161

Joachim Ansorg edited this page 2021-11-12 19:41:43 +01:00

Table of Contents

• Instead of [ 1 ], use true.
• Problematic code:
• Correct code:
• Rationale:
• Exceptions:

Instead of [ 1 ], use true.

Problematic code:

while [ 1 ]
do
  echo "infinite loop"
done

Correct code:

while true
do
  echo "infinite loop"
done

Rationale:

This is a stylistic suggestion to use true instead of [ 1 ].

[ 1 ] seems to suggest that the value "1" is somehow relevant to the statement. This is not the case: it doesn't matter. You can replace it with [ 0 ] or [ wombat ], and it will still always be true.

If you instead use true, the value is actually considered and can be inverted by replacing with false.

On bash, you can also use (( 1 )), which evaluates to true much like in C. (( 0 )) is similarly false.

Exceptions:

None.

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