clump: fix empty sequence input. rephrase docs a bit

db4
Jon Harper 2012-10-28 15:28:05 +01:00 committed by Doug Coleman
parent 2fc1442771
commit 7b7586fa54
2 changed files with 4 additions and 2 deletions

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@ -117,7 +117,7 @@ $nl
HELP: clump
{ $values { "seq" "a sequence" } { "n" "a non-negative integer" } { "array" "a sequence of sequences" } }
{ $description "Splits the sequence into overlapping clumps of " { $snippet "n" } " elements and collects the clumps into a new array." }
{ $notes "If the sequence length is smaller than " { $snippet "n" } ", the result will be an array with one element: the original sequence " { $snippet "seq" } "." }
{ $notes "For an empty sequence, the result is an empty sequence. For a non empty sequence with a length smaller than " { $snippet "n" } ", the result will be a sequence with one element: the input sequence " { $snippet "seq" } "." }
{ $examples
{ $example "USING: grouping prettyprint ;" "{ 3 1 3 3 7 } 2 clump ." "{ { 3 1 } { 1 3 } { 3 3 } { 3 7 } }" }
} ;

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@ -44,7 +44,9 @@ MIXIN: abstract-clumps
INSTANCE: abstract-clumps sequence
M: abstract-clumps length
[ seq>> length 1 + ] [ n>> ] bi - 1 max ; inline
dup seq>> length [ drop 0 ] [
swap [ 1 + ] [ n>> ] bi* - 1 max
] if-zero ; inline
M: abstract-clumps set-length
[ n>> + 1 - ] [ seq>> ] bi set-length ; inline