Understanding environment variable / shell syntax
Clash Royale CLAN TAG#URR8PPP
I was just following the install instructions for zsh-autosuggestions and I don't understand what part of the following command is doing:
git clone https://github.com/zsh-users/zsh-autosuggestions $ZSH_CUSTOM:-~/.oh-my-zsh/custom/plugins/zsh-autosuggestions
- What does the
$ZSH_CUSTOM:- ...do? - Why not just clone directly into
~/.oh-my-zsh/...?
terminal zsh git
asked Jan 27 at 18:20
skubeskube
1083
add a comment |
I was just following the install instructions for zsh-autosuggestions and I don't understand what part of the following command is doing:
git clone https://github.com/zsh-users/zsh-autosuggestions $ZSH_CUSTOM:-~/.oh-my-zsh/custom/plugins/zsh-autosuggestions
- What does the
$ZSH_CUSTOM:- ...do? - Why not just clone directly into
~/.oh-my-zsh/...?
terminal zsh git
asked Jan 27 at 18:20
skubeskube
1083
add a comment |
I was just following the install instructions for zsh-autosuggestions and I don't understand what part of the following command is doing:
git clone https://github.com/zsh-users/zsh-autosuggestions $ZSH_CUSTOM:-~/.oh-my-zsh/custom/plugins/zsh-autosuggestions
- What does the
$ZSH_CUSTOM:- ...do? - Why not just clone directly into
~/.oh-my-zsh/...?
terminal zsh git
asked Jan 27 at 18:20
skubeskube
1083
I was just following the install instructions for zsh-autosuggestions and I don't understand what part of the following command is doing:
git clone https://github.com/zsh-users/zsh-autosuggestions $ZSH_CUSTOM:-~/.oh-my-zsh/custom/plugins/zsh-autosuggestions
- What does the
$ZSH_CUSTOM:- ...do? - Why not just clone directly into
~/.oh-my-zsh/...?
terminal zsh git
terminal zsh git
asked Jan 27 at 18:20
skubeskube
1083
asked Jan 27 at 18:20
skubeskube
1083
asked Jan 27 at 18:20
skubeskube
1083
asked Jan 27 at 18:20
skubeskube
1083
asked Jan 27 at 18:20
skubeskube
1083
1083
add a comment |
add a comment |
1 Answer
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The parameter substitution $variable:-value would be replaced by $variable if that variable was set and not empty, otherwise it's replaced by value. This is a standard parameter expansion.
In this case, it allows the user to set ZSH_CUSTOM to where they keep their oh-my-zsh customisation files, or to not set it and use the default location of ~/.oh-my-zsh/custom.
Not using this construct would make the life of users who have tailor made setups a bit awkward as they would have to either manually modify the command, or move the files to the correct place after installation (and possibly run the risk of having pre-existing files overwritten by git clone).
answered Jan 27 at 18:58
KusalanandaKusalananda
130k17246406
add a comment |
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1 Answer
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1 Answer
1
active
oldest
votes
active
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active
oldest
votes
The parameter substitution $variable:-value would be replaced by $variable if that variable was set and not empty, otherwise it's replaced by value. This is a standard parameter expansion.
In this case, it allows the user to set ZSH_CUSTOM to where they keep their oh-my-zsh customisation files, or to not set it and use the default location of ~/.oh-my-zsh/custom.
Not using this construct would make the life of users who have tailor made setups a bit awkward as they would have to either manually modify the command, or move the files to the correct place after installation (and possibly run the risk of having pre-existing files overwritten by git clone).
answered Jan 27 at 18:58
KusalanandaKusalananda
130k17246406
add a comment |
The parameter substitution $variable:-value would be replaced by $variable if that variable was set and not empty, otherwise it's replaced by value. This is a standard parameter expansion.
In this case, it allows the user to set ZSH_CUSTOM to where they keep their oh-my-zsh customisation files, or to not set it and use the default location of ~/.oh-my-zsh/custom.
Not using this construct would make the life of users who have tailor made setups a bit awkward as they would have to either manually modify the command, or move the files to the correct place after installation (and possibly run the risk of having pre-existing files overwritten by git clone).
answered Jan 27 at 18:58
KusalanandaKusalananda
130k17246406
add a comment |
The parameter substitution $variable:-value would be replaced by $variable if that variable was set and not empty, otherwise it's replaced by value. This is a standard parameter expansion.
In this case, it allows the user to set ZSH_CUSTOM to where they keep their oh-my-zsh customisation files, or to not set it and use the default location of ~/.oh-my-zsh/custom.
Not using this construct would make the life of users who have tailor made setups a bit awkward as they would have to either manually modify the command, or move the files to the correct place after installation (and possibly run the risk of having pre-existing files overwritten by git clone).
answered Jan 27 at 18:58
KusalanandaKusalananda
130k17246406
The parameter substitution $variable:-value would be replaced by $variable if that variable was set and not empty, otherwise it's replaced by value. This is a standard parameter expansion.
In this case, it allows the user to set ZSH_CUSTOM to where they keep their oh-my-zsh customisation files, or to not set it and use the default location of ~/.oh-my-zsh/custom.
Not using this construct would make the life of users who have tailor made setups a bit awkward as they would have to either manually modify the command, or move the files to the correct place after installation (and possibly run the risk of having pre-existing files overwritten by git clone).
answered Jan 27 at 18:58
KusalanandaKusalananda
130k17246406
edited Jan 27 at 19:04
answered Jan 27 at 18:58
KusalanandaKusalananda
130k17246406
answered Jan 27 at 18:58
KusalanandaKusalananda
130k17246406
answered Jan 27 at 18:58
KusalanandaKusalananda
130k17246406
130k17246406
add a comment |
add a comment |
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