Small updates. Regenerate example/int.go.

btree.go

@@ -2,58 +2,6 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Package b implements a B+tree.
-//
-// Changelog
-//
-// 2014-06-26: Lower GC presure by recycling things.
-//
-// 2014-04-18: Added new method Put.
-//
-// Generic types
-//
-// Keys and their associated values are interface{} typed, similar to all of
-// the containers in the standard library.
-//
-// Semiautomatic production of a type specific variant of this package is
-// supported via
-//
-//	$ make generic
-//
-// This command will write to stdout a version of the btree.go file where
-// every key type occurrence is replaced by the word 'key' (written in all
-// CAPS) and every value type occurrence is replaced by the word 'value'
-// (written in all CAPS). Then you have to replace these tokens with your
-// desired type(s), using any technique you're comfortable with.
-//
-// This is how, for example, 'example/int.go' was created:
-//
-//	$ mkdir example
-//	$
-//	$ # Note: the command below must be actually written using the words
-//	$ # 'key' and 'value' in all CAPS. The proper form is avoided in this
-//	$ # documentation to not confuse any text replacement mechanism.
-//	$
-//	$ make generic | sed -e 's/key/int/g' -e 's/value/int/g' > example/int.go
-//
-// No other changes to int.go are necessary, it compiles just fine.
-//
-// Running the benchmarks for 1000 keys on a machine with Intel i5-4670 CPU @
-// 3.4GHz, Go release 1.3.
-//
-//	$ go test -bench 1e3 example/all_test.go example/int.go
-//	PASS
-//	BenchmarkSetSeq1e3	   10000	    146740 ns/op
-//	BenchmarkGetSeq1e3	   10000	    108261 ns/op
-//	BenchmarkSetRnd1e3	   10000	    254359 ns/op
-//	BenchmarkGetRnd1e3	   10000	    134621 ns/op
-//	BenchmarkDelRnd1e3	   10000	    211864 ns/op
-//	BenchmarkSeekSeq1e3	   10000	    148628 ns/op
-//	BenchmarkSeekRnd1e3	   10000	    215166 ns/op
-//	BenchmarkNext1e3	  200000	      9211 ns/op
-//	BenchmarkPrev1e3	  200000	      8843 ns/op
-//	ok  	command-line-arguments	25.071s
-//	$
 package b
 
 import (

doc.go

+// Copyright 2014 The b Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package b implements a B+tree.
+//
+// Changelog
+//
+// 2014-06-26: Lower GC presure by recycling things.
+//
+// 2014-04-18: Added new method Put.
+//
+// Generic types
+//
+// Keys and their associated values are interface{} typed, similar to all of
+// the containers in the standard library.
+//
+// Semiautomatic production of a type specific variant of this package is
+// supported via
+//
+//	$ make generic
+//
+// This command will write to stdout a version of the btree.go file where every
+// key type occurrence is replaced by the word 'KEY' and every value type
+// occurrence is replaced by the word 'VALUE'. Then you have to replace these
+// tokens with your desired type(s), using any technique you're comfortable
+// with.
+//
+// This is how, for example, 'example/int.go' was created:
+//
+//	$ mkdir example
+//	$ make generic | sed -e 's/KEY/int/g' -e 's/VALUE/int/g' > example/int.go
+//
+// No other changes to int.go are necessary, it compiles just fine.
+//
+// Running the benchmarks for 1000 keys on a machine with Intel i5-4670 CPU @
+// 3.4GHz, Go release 1.4.2.
+//
+//	$ go test -bench 1e3 example/all_test.go example/int.go
+//	PASS
+//	BenchmarkSetSeq1e3	   10000	    151620 ns/op
+//	BenchmarkGetSeq1e3	   10000	    115354 ns/op
+//	BenchmarkSetRnd1e3	    5000	    255865 ns/op
+//	BenchmarkGetRnd1e3	   10000	    140466 ns/op
+//	BenchmarkDelSeq1e3	   10000	    143860 ns/op
+//	BenchmarkDelRnd1e3	   10000	    188228 ns/op
+//	BenchmarkSeekSeq1e3	   10000	    156448 ns/op
+//	BenchmarkSeekRnd1e3	   10000	    190587 ns/op
+//	BenchmarkNext1e3	  200000	      9407 ns/op
+//	BenchmarkPrev1e3	  200000	      9306 ns/op
+//	ok  	command-line-arguments	26.369s
+//	$
+package b

example/int.go

@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Package b implements a int->int B+tree.
 package b
 
 import (
@@ -234,17 +233,18 @@ func (t *Tree) cat(p *x, q, r *d, pi int) {
 	if p.c > 1 {
 		p.extract(pi)
 		p.x[pi].ch = q
-	} else {
-		switch x := t.r.(type) {
-		case *x:
-			*x = zx
-			btXPool.Put(x)
-		case *d:
-			*x = zd
-			btDPool.Put(x)
-		}
-		t.r = q
+		return
+	}
+
+	switch x := t.r.(type) {
+	case *x:
+		*x = zx
+		btXPool.Put(x)
+	case *d:
+		*x = zd
+		btDPool.Put(x)
 	}
+	t.r = q
 }
 
 func (t *Tree) catX(p, q, r *x, pi int) {
@@ -462,10 +462,11 @@ func (t *Tree) overflow(p *x, q *d, pi, i int, k int, v int) {
 			q.mvR(r, 1)
 			t.insert(q, i, k, v)
 			p.x[pi].k = r.d[0].k
-		} else {
-			t.insert(r, 0, k, v)
-			p.x[pi].k = k
+			return
 		}
+
+		t.insert(r, 0, k, v)
+		p.x[pi].k = k
 		return
 	}
 
@@ -586,9 +587,9 @@ func (t *Tree) Set(k int, v int) {
 // (whatever, false) if it decides not to create or not to update the value of
 // the KV pair.
 //
-// 	tree.Set(k, v) conceptually equals
+// 	tree.Set(k, v) call conceptually equals calling
 //
-// 	tree.Put(k, func(k, v []byte){ return v, true }([]byte, bool))
+// 	tree.Put(k, func(int, bool){ return v, true })
 //
 // modulo the differing return values.
 func (t *Tree) Put(k int, upd func(oldV int, exists bool) (newV int, write bool)) (oldV int, written bool) {
@@ -739,15 +740,22 @@ func (t *Tree) underflow(p *x, q *d, pi int) {
 	if l != nil && l.c+q.c >= 2*kd {
 		l.mvR(q, 1)
 		p.x[pi-1].k = q.d[0].k
-	} else if r != nil && q.c+r.c >= 2*kd {
+		return
+	}
+
+	if r != nil && q.c+r.c >= 2*kd {
 		q.mvL(r, 1)
 		p.x[pi].k = r.d[0].k
 		r.d[r.c] = zde // GC
-	} else if l != nil {
+		return
+	}
+
+	if l != nil {
 		t.cat(p, l, q, pi-1)
-	} else {
-		t.cat(p, q, r, pi)
+		return
 	}
+
+	t.cat(p, q, r, pi)
 }
 
 func (t *Tree) underflowX(p *x, q *x, pi int, i int) (*x, int) {