| 1 | #!/usr/bin/env bash
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| 2 | #
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| 3 | # Usage:
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| 4 | #   ./01-char-class.sh <function name>
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| 5 | 
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| 6 | set -o nounset
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| 7 | set -o pipefail
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| 8 | set -o errexit
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| 9 | 
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| 10 | demo() {
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| 11 |   [[ a == [a] ]]
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| 12 |   [[ a != [^a] ]]
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| 13 | 
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| 14 |   [[ a == [ab] ]]
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| 15 |   [[ a != [^ab] ]]
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| 16 | 
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| 17 |   [[ a == [[:alpha:]] ]]
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| 18 |   [[ a != [^[:alpha:]] ]]
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| 19 |   [[ 0 == [^[:alpha:]] ]]
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| 20 | 
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| 21 |   # NOTE: there is only one negation.  You can't mix them.
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| 22 |   [[ 0 == [^[:alpha:]] ]]
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| 23 | 
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| 24 |   if test -n "${BASH_VERSION:-}"; then
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| 25 |     #echo hi
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| 26 |     true
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| 27 |   fi
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| 28 | 
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| 29 |   echo
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| 30 |   echo 'ALL PASSED'
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| 31 | }
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| 32 | 
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| 33 | "$@"
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