37 lines
661 B
Markdown
37 lines
661 B
Markdown
# Curly brace
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> Multipurpose shell syntax.
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> More information: <https://www.gnu.org/software/bash/manual/bash.html#index-hash>.
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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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- Capitalize all the characters:
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`echo ${variable^^}`
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