setf

setf( 
g_place 
g_value 
) 
=> g_result

setf( 
g_place := g_value
=> g_result

Description

Assigns a new value to an existing storage location, destroying the value that was previously in that location. setf is the same as the assignment (:=) operator. This is a syntax form.

The setf function uses special expander functions, defined as setf_<helper>.

Arguments

g_place	Specifies the storage location
g_value	Specifies the new value

Value Returned

g_result

Returns the updated result

Examples

x = '(a b c d e)
setf( (car x) 42);; here x changes to (42 b c d e)
=> (42 b c d e)

x = '(a b c d e)
(car x) := 42
x 
=> (42 b c d e)

Related Topics

pushf

popf

setf Helper Functions

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