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43 lines
1.1 KiB
Plaintext
43 lines
1.1 KiB
Plaintext
---
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syntax: markdown
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tags: [tldr, common]
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source: https://github.com/tldr-pages/tldr.git
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---
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# [[
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> Check file types and compare values.
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> Returns a status of 0 if the condition evaluates to true, 1 if it evaluates to false.
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> More information: <https://gnu.org/software/bash/manual/bash.html#index-_005b_005b>.
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- Test if a given variable is equal to the specified string or glob:
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`[[ ${{variable}} == "{{string}}" ]]`
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- Test if a given string conforms the specified `regex`:
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`[[ ${{variable}} =~ {{pattern}} ]]`
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- Test if a given variable is [eq]ual/[n]ot [e]qual/[g]reater [t]han/[l]ess [t]han/[g]reater than or [e]qual/[l]ess than or [e]qual to the specified number:
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`[[ ${{variable}} -{{eq|ne|gt|lt|ge|le}} {{integer}} ]]`
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- Test if the specified variable has a [n]on-empty value:
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`[[ -n ${{variable}} ]]`
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- Test if the specified variable has an empty value ([z]ero length):
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`[[ -z ${{variable}} ]]`
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- Test if the specified [f]ile exists:
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`[[ -f {{path/to/file}} ]]`
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- Test if the specified [d]irectory exists:
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`[[ -d {{path/to/directory}} ]]`
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- Test if the specified file or directory [e]xists:
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`[[ -e {{path/to/file_or_directory}} ]]`
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