在单行 Bash 脚本中设置变量
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Setting a variable in a one-liner Bash script
提问by user3349369
Looking for a way to set a variable, in a bash one-liner, that is a script, such as:
寻找一种设置变量的方法，在 bash 单行中，即脚本，例如：
export class={read -p "What Is Your Profession?" a; case $a in "Theif") echo "Stealth" ; in "Cleric") echo "Heals?" ; "Monk") echo "Focus?" ; *) echo "invalid choice" a; esac}
Although I'm having issues running this command without setting it to a one-liner, I've tried it numerous ways and I have gotten no results. The above was just the most clearly laid out in my eyes. I've also tried VAR= ,
尽管我在不将其设置为单行命令的情况下运行此命令时遇到问题，但我已经尝试了多种方法，但没有得到任何结果。以上只是我眼中最清楚的布局。我也试过VAR= ,
The case itself gives me a
案例本身给了我一个
-jailshell: syntax error near unexpected token `('
whenever I run it with more than one case. I know this is probably all jumbled up.
每当我用多个案例运行它时。我知道这可能都是乱七八糟的。
回答by Jonathan Leffler
You need double-semicolons ;;to separate the clauses of a casestatement, whether it is one line or many. You also have to be careful with { … }because it is used for I/O redirection. Further, both {and }must be tokens at the start of a command; there must be a space (or newline) after {and a semicolon (or ampersand, or newline) before }. Even with that changed, the assignment would not execute the code in between the braces. For that, you could use command substitution:
无论是一行还是多行，您都需要双分号;;来分隔case语句的子句。您还必须小心，{ … }因为它用于 I/O 重定向。此外，{和}必须是命令开头的标记；之后必须有一个空格（或换行符）{，之前必须有一个分号（或与号，或换行符）}。即使更改了，赋值也不会执行大括号之间的代码。为此，您可以使用命令替换：
export class=$(read -p "What Is Your Profession?" a; case $a in "Theif") echo "Stealth" ;; "Cleric") echo "Heals?" ;; "Monk") echo "Focus?" ;; *) echo "invalid choice $a";; esac)
Finally, you've not run a spell-check on 'Thief'.
最后，您还没有对“小偷”进行拼写检查。
回答by anubhava
Here is one-liner you can use:
这是您可以使用的单线：
export class=`{ read -p "What Is Your Profession? " a; case $a in "Theif") echo "Stealth";; "Cleric") echo "Heals?";; "Monk") echo "Focus?";; *) echo "invalid choice" a;; esac; }`
OR better you can just put this inside a function:
或者更好的是你可以把它放在一个函数中：
function readclass() { read -p "What Is Your Profession? " a; case $a in "Theif") echo "Stealth";; "Cleric") echo "Heals?";; "Monk") echo "Focus?";; *) echo "invalid choice" a;; esac; }
Then use it:
然后使用它：
export class=$(readclass)
