CLHS: Function ZEROP

#

Function ZEROP

Syntax:

zerop number => generalized-boolean

Pronunciation:

['zee(,)roh(,)pee]

Arguments and Values:

number---a number.

generalized-boolean---a generalized boolean.

Description:

Returns true if number is zero (integer, float, or complex); otherwise, returns false.

Regardless of whether an implementation provides distinct representations for positive and negative floating-point zeros, `(zerop -0.0)` always returns true.

Examples:

     (zerop 0) =>  true
     (zerop 1) =>  false
     (zerop -0.0) =>  true
     (zerop 0/100) =>  true
     (zerop #c(0 0.0)) =>  true

Side Effects: None.

Affected By: None.

Exceptional Situations:

Should signal an error of type type-error if number is not a number.

See Also: None.

Notes:

     (zerop number) ==  (= number 0)

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