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Rebol Programming/alter
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USAGE:
ALTER series value /case
DESCRIPTION:
If a value is not found in a series, append it; otherwise, remove it. Returns true if added. (Modifies)
ALTER is a function value.
ARGUMENTS
series -- (Type: series port)
value -- (Type: any)
REFINEMENTS
/case -- Case-sensitive comparison
SOURCE CODE
alter: func [
{If a value is not found in a series, append it; otherwise, remove it. Returns true if added. (Modifies)}
series [series! port!]
value
/case "Case-sensitive comparison"
][
found? unless remove (
either case [find/case series :value] [find series :value]
) [append series :value]
]