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multiple-value-prog1 Data and Control Flow Dictionary values
Macro

multiple-value-setq

multiple-value-setq vars form ⇒ result

Arguments and Values

varsa list of symbols that are either variable names or names of symbol macros.
forma form.
resultThe primary value returned by the form.

Description

multiple-value-setq assigns values to vars.

The form is evaluated, and each var is assigned to the corresponding value returned by that form. If there are more vars than values returned, nil is assigned to the extra vars. If there are more values than vars, the extra values are discarded.

If any var is the name of a symbol macro, then it is assigned as if by setf. Specifically, 

 (multiple-value-setq (symbol_1 ... symbol_n) value-producing-form)

is defined to always behave in the same way as 

 (values (setf (values symbol_1 ... symbol_n) value-producing-form))

in order that the rules for order of evaluation and side-effects be consistent with those used by setf.

See VALUES Forms as Places.

Examples

 (multiple-value-setq (quotient remainder) (truncate 3.2 2)) ⇒  1
 quotient ⇒  1
 remainder ⇒  1.2
 (multiple-value-setq (a b c) (values 1 2)) ⇒  1
 a ⇒  1
 b ⇒  2
 c ⇒  NIL
 (multiple-value-setq (a b) (values 4 5 6)) ⇒  4
 a ⇒  4
 b ⇒  5

See Also

setq, symbol-macrolet

Backlinks

Data and Control Flow Dictionary, define-symbol-macro, multiple-values-limit, Return Values, symbol-macrolet, Symbols as Forms, Symbols in the COMMON-LISP Package