将函数存储在unix变量中 [英] store a function in a unix variable
问题描述
我是Unix的新手.我想知道是否可以将函数分配给unix变量,例如:
temp = funcname(){echo'我在功能中'};$ temp;//打印我在运行.
请让我知道.
在UNIX shell中,函数不是一流的.但是,您可以将函数的名称存储在shell变量中,然后调用它.
funcname_foo(){回声我是一个功能"}temp =功能名称_foo"$ temp"
也就是说-如果您想有条件地指向其他函数,则可以轻松地有条件地定义它:
if ["$ foo" = bar];然后funcname(){echo"Function A";}别的funcname(){echo"Function B";}科幻funcname#实际调用函数
可以通过使用 eval
使用变量中的文本来定义函数;但是,这是容易出错且与最佳做法相反的,通常不应这样做./p>
如果您描述了您的实际用例,那么应该有一个更好的例子来说明达到所需结果的正确方法.
I am a newbie to unix. I am wondering if there is any way to assign a function to a unix variable, like:
temp=funcname(){echo 'I am in function'};
$temp; // prints I am in function.
Please let me know.
Functions are not first-class in UNIX shells. However, you can store the name of your function in a shell variable and call it thereby.
funcname_foo() {
echo "I am a function"
}
temp=funcname_foo
"$temp"
That said -- if you wanted to point to a different function conditionally, you could just as easily define it conditionally:
if [ "$foo" = bar ] ; then
funcname() { echo "Function A"; }
else
funcname() { echo "Function B"; }
fi
funcname # actually call the function
It is possible to define a function using text from a variable through use of eval
; however, this is error-prone and contrary to best practices, and generally should not be done.
If you described your actual use case, a better example of the right way to achieve your desired result should be possible.
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