12.2.18 zerop [Function]

zerop number ⇒ generalized-boolean

Pronunciation::

pronounced ’z\=e (, )r\=o(, )p\=e

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

Exceptional Situations::

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

Notes::

 (zerop number) ≡ (= number 0)