How can you write multiple statements in elisp 'if' statement?

问题

In elisp, there is an 'if' case where I would like to perform many different things:

(if condition
    (do-something)
    (do-something-else)
    ...)

However, (do-something-else) is executed in the else-case only. How can you specify a block of instructions to execute? For example:

(if condition
    (begin
        (do-something)
        (do-something-else)
        ...))

回答1:

Use progn:

(if condition
    (progn
        (do-something)
        (do-something-else)))

回答2:

If there's no else required, it might be more readable to use:

(when condition
    (do-something)
    (do-something-else))

And, there's the converse

(unless (not condition)
    (do-something)
    (do-something-else))

Check out the Emacs Lisp manual for conditionals.

来源：https://stackoverflow.com/questions/912355/how-can-you-write-multiple-statements-in-elisp-if-statement