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42 lines
804 B
Plaintext
42 lines
804 B
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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> Multipurpose shell syntax.
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> More information: <https://www.gnu.org/software/bash/manual/bash.html>.
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- Isolate variable names:
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`echo ${{{HOME}work}}`
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- Brace expand sequences:
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`echo {{{1..3}}} {{{a..c}}}{{{dir1,dir2,dir3}}}`
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- Check if `variable` is set before returning text:
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`echo ${{{variable:+variable is set and contains $variable}}}`
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- Set default values in case `variable` is unset:
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`echo ${{{variable:-default}}}`
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- Return `variable` length in characters:
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`echo ${{{#variable}}}`
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- Return a string slice:
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`echo ${{{variable:3:7}}}`
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- Recursively expand a `variable`:
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`echo ${{{!variable}}}`
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- Group command output together:
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`{ {{command1; command2; ...}} } | {{another_command}}`
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