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Rebol Programming/mod
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USAGE:
MOD a b
DESCRIPTION:
Compute a nonnegative remainder of A divided by B.
MOD is a function value.
ARGUMENTS:
a -- (Type: number money time)
b -- Must be nonzero. (Type: number money time)
(SPECIAL ATTRIBUTES)
catch
SOURCE CODE
mod: func [
"Compute a nonnegative remainder of A divided by B."
[catch]
a [number! money! time!]
b [number! money! time!] "Must be nonzero."
/local r
][
all [negative? r: a // b r: r + b]
a: abs a
either all [a + r = (a + b) positive? r + r - b] [r - b] [r]
]