如何显示 zsh 函数定义(如 bash“ type myfunc”) ？

如何在 zsh 中显示函数的定义? type foo没有给出定义。

在 bash 中:

bash$ function foo() { echo hello; }


bash$ foo
hello


bash$ type foo
foo is a function
foo ()
{
echo hello
}

在 zsh 中:

zsh$ function foo() { echo hello; }


zsh$ foo
hello


zsh$ type foo
foo is a shell function
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最佳答案

The zsh idiom is whence, the -f flag prints function definitions:

zsh$ whence -f foo
foo () {
echo hello
}
zsh$

In zsh, type is defined as equivalent to whence -v, so you can continue to use type, but you'll need to use the -f argument:

zsh$ type -f foo
foo () {
echo hello
}
zsh$

And, finally, in zsh which is defined as equivalent to whence -c - print results in csh-like format, so which foo will yield the same results.

man zshbuiltins for all of this.

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I've always just used which for this.

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If you're not quite sure what you are looking for, you can type just

functions

and it will show you all the defined functions.

Note that there are sometimes a LOT of them, so you might want to pipe to a pager program:

functions | less

to undefine a function, use

unfunction functionname
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tl;dr

declare -f foo  # works in zsh and bash


typeset -f foo  # works in zsh, bash, and ksh

If you don't mind or prefer including all command forms that exist for a given name in the output:Thanks, Raine Revere.

type -af  # zsh only (works differently in bash and ksh)

type -f / whence -f / which are suboptimal in this case, because their purpose is to report the command form with the highest precedence that happens to be defined by that name - as opposed to specifically reporting on the operand as a function.

That said, in practice this means that only an alias of the same name takes precedence (and technically also a shell keyword, though naming functions for shell keywords is probably a bad idea anyway).

Note that zsh does expand aliases in scripts by default (as does ksh, but not bash), and even if you turn alias expansion off first, type -f / whence -f / which still report aliases first.

In zsh, the -f option only includes shell functions in the lookup in zsh, so - unless -a is also used to list all command forms - an alias by the given name would print as the only output.

In bash and ksh, type -f actually excludes functions from the lookup; whence doesn't exist in bash, and in ksh it doesn't print the function ksh0; which is not a builtin in ksh and bash, and the external utility by definition cannot print shell functions.


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