CLHS: Function -

#

Function -

Syntax:

- number => negation

- minuend `&rest` subtrahends+ => difference

Arguments and Values:

number, minuend, subtrahend---a number.

negation, difference---a number.

Description:

The function - performs arithmetic subtraction and negation.

If only one number is supplied, the negation of that number is returned.

If more than one argument is given, it subtracts all of the subtrahends from the minuend and returns the result.

The function - performs necessary type conversions.

Examples:

     (- 55.55) =>  -55.55
     (- #c(3 -5)) =>  #C(-3 5)
     (- 0) =>  0
     (eql (- 0.0) -0.0) =>  true
     (- #c(100 45) #c(0 45)) =>  100
     (- 10 1 2 3 4) =>  0

Affected By: None.

Exceptional Situations:

Might signal type-error if some argument is not a number. Might signal arithmetic-error.

See Also:

Section 12.1.1 (Numeric Operations), Section 12.1.3 (Rational Computations), Section 12.1.4 (Floating-point Computations), Section 12.1.5 (Complex Computations)

Notes: None.

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