digit-value -- r7rs Definition

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Kind

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converter;

Implemented by

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• digit-value (from vonuvoli);

Procedure signature

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Procedure variants:

• ((character-ascii-numeric) -> (exact-integer-positive-or-zero))
  • input: a value of type character-ascii-numeric;
  • output: a value of type exact-integer-positive-or-zero;
• ((character-numeric) -> (exact-integer-positive-or-zero))
  • input: a value of type character-numeric;
  • output: a value of type exact-integer-positive-or-zero;
• ((character) -> (false))
  • input: a value of type character;
  • output: a value of type false;

Exports

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• scheme:char -- (scheme char);

Exports recursive

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• scheme -- (scheme);

Description

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(digit-value char)

This procedure returns the numeric value (0 to 9) of its argument if it is a numeric digit (that is, if char-numeric? returns #t), or #f on any other character.

(digit-value #\3)      ===>  3
(digit-value #\x0664)  ===>  4
(digit-value #\x0AE6)  ===>  0
(digit-value #\x0EA6)  ===>  #f

---

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

Referenced-types

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• character-ascii-numeric;
• exact-integer-positive-or-zero;
• character-numeric;
• character;
• false;