- -- r7rs Definition

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Kind

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procedure;

Implemented by

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• - (from vonuvoli);

Procedure signature

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Procedure variants:

• ((number-zero) -> (number-zero))
  • input: a value of type number-zero;
  • output: a value of type number-zero;
• ((number-positive) -> (number-negative))
  • input: a value of type number-positive;
  • output: a value of type number-negative;
• ((number-negative) -> (number-positive))
  • input: a value of type number-negative;
  • output: a value of type number-positive;
• ((number-not-nan |2...|) -> (number))
  • inputs:
    • a value of type number-not-nan;
    • ... -- at least 2 times;
  • output: a value of type number;
• ((number |1...|) -> (number-nan))
  • inputs:
    • a value of type number;
    • ... -- at least one time;
  • output: a value of type number-nan;

Exports

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• scheme:base -- (scheme base);

Exports recursive

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• scheme -- (scheme);

Description

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(- z)
(- z_1 z_2 ...)
(/ z)
(/ z_1 z_2 ...)

With two or more arguments, these procedures return the difference or quotient of their arguments, associating to the left. With one argument, however, they return the additive or multiplicative inverse of their argument.

It is an error if any argument of / other than the first is an exact zero. If the first argument is an exact zero, an implementation may return an exact zero unless one of the other arguments is a NaN.

(- 3 4)                 ===>  -1
(- 3 4 5)               ===>  -6
(- 3)                   ===>  -3
(/ 3 4 5)               ===>   3/20
(/ 3)                   ===>   1/3

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The text herein was sourced and adapted as described in the "R7RS attribution of various text snippets" appendix.

Referenced-types

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• number-zero;
• number-positive;
• number-negative;
• number-not-nan;
• number;
• number-nan;