==>: Indicating an Expansion

When an expression is a macro call, it expands into a new expression. You can indicate the result of the expansion with the @expansion{} command.

The @expansion{} command is displayed as `==>' in Info and as `==>' in the printed output.

For example, the following

@lisp
(third '(a b c))
     @expansion{} (car (cdr (cdr '(a b c))))
     @result{} c
@end lisp

produces

(third '(a b c))
     ==> (car (cdr (cdr '(a b c))))
     => c

which may be read as:

(third '(a b c)) expands to (car (cdr (cdr '(a b c)))); the result of evaluating the expression is c.

Often, as in this case, an example looks better if the @expansion{} and @result{} commands are indented five spaces.

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