设置-e和短期测试
问题说明
当我是新来的shell脚本，我用了很多的短期测试，而不是如果语句，如假放;＆安培;真正。
When I was new to shell scripting, I used a lot of short tests instead of if statements, like false && true.
再后来我学会了使用设置-e 时，发现我的脚本是死于因某种原因，如果我取代了简短的测试以饱满他们将努力如果语句。现在，时代已经一去不复返了，而我还在用充满如果语句只。
Then later I learned using set -e, and found my scripts were dying for some reason, and they would work if I replaced the short tests with full if statements. Now, the time has gone, and I still use full if statements only.
最有趣的是，如果我打开一个交互的shell并执行以下操作：
The most interesting is that if I open an interactive shell and do the following:
set -e
false && true
echo $?
则返回1，但shell不会死！
我看到，我已经浪费了code过多的线条。我该如何使用设置-e 短的测试安全，如任何人都可以向我解释。没有剧本死去？
I see that I have been wasting too many lines of code. Anyone could explain to me how can I use set -e with short tests safely, eg. without the script dying?
正确答案
对于我的剧本意外死去的问题，这是由于在子shell中运行这些短期测试。
Regarding my problem of the script unexpectedly dying, it is due to running those short tests in a subshell.
原来的例子：
$ set -e
$ false && true
$ echo $?
1
使用子shell：
Using a subshell:
$ set -e
$ (false && true)
<script died>
$ set -e
$ variable=$(false && true)
<script died>
$ set -e
$ foo()(false && true)
$ foo
<script died>
$ set -e
$ foo(){ false && true; }
$ foo
<script died>
可能的解决方案：
Possible solutions:
$ set -e
$ (false && true ||:)
$ (false && true) ||:
$ (if false; then true; fi)
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