51 lines
1.2 KiB
Clojure
51 lines
1.2 KiB
Clojure
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(ns clojure.core.protocols)
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(set! *warn-on-reflection* true)
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(defprotocol CollReduce
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"Protocol for collection types that can implement reduce faster than
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first/next recursion. Called by clojure.core/reduce. Baseline
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implementation defined in terms of Iterable."
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(coll-reduce [coll f] [coll f val]))
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(defprotocol
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InternalReduce
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"Protocol for concrete seq types that can reduce themselves
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faster than first/next recursion. Called by clojure.core/reduce."
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(internal-reduce [seq f start]))
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(defn- seq-reduce
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([coll f]
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(if-let [s (seq coll)]
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(internal-reduce (next s) f (first s))
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(f)))
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([coll f val]
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(let [s (seq coll)]
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(internal-reduce s f val))))
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(defn- iter-reduce
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([^java.lang.Iterable coll f]
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(let [iter (.iterator coll)]
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(if (.hasNext iter)
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(loop [ret (.next iter)]
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(if (.hasNext iter)
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(let [ret (f ret (.next iter))]
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(if (reduced? ret)
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@ret
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(recur ret)))
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ret))
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(f))))
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([^java.lang.Iterable coll f val]
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(let [iter (.iterator coll)]
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(loop [ret val]
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(if (.hasNext iter)
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(let [ret (f ret (.next iter))]
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(if (reduced? ret)
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@ret
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(recur ret)))
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ret)))))
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