multi-test dans bash avec double crochets

Code:

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$ help '[['
[[ ... ]]: [[ expression ]]
    Execute conditional command.

    Returns a status of 0 or 1 depending on the evaluation of the conditional
    expression EXPRESSION.  Expressions are composed of the same primaries used
    by the `test' builtin, and may be combined using the following operators:

      ( EXPRESSION )    Returns the value of EXPRESSION
      ! EXPRESSION              True if EXPRESSION is false; else false
      EXPR1 && EXPR2    True if both EXPR1 and EXPR2 are true; else false
      EXPR1 || EXPR2    True if either EXPR1 or EXPR2 is true; else false

    When the `==' and `!=' operators are used, the string to the right of
    the operator is used as a pattern and pattern matching is performed.
    When the `=~' operator is used, the string to the right of the operator
    is matched as a regular expression.

    The && and || operators do not evaluate EXPR2 if EXPR1 is sufficient to
    determine the expression's value.

    Exit Status:
    0 or 1 depending on value of EXPRESSION.

donc

Code:

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$ nb=5 ; [[ $nb -ge 3 && $nb -le 7 ]] && echo yes || echo no
yes

ou même (le principe des doubles crochets) :

Code:

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$ nb=5 ; [[ nb -ge 3 && nb -le 7 ]] && echo yes || echo no
yes