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+// Copyright (c) 2016 Uber Technologies, Inc.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+// Package zap provides fast, structured, leveled logging.
+//
+// For applications that log in the hot path, reflection-based serialization
+// and string formatting are prohibitively expensive - they're CPU-intensive
+// and make many small allocations. Put differently, using json.Marshal and
+// fmt.Fprintf to log tons of interface{} makes your application slow.
+//
+// Zap takes a different approach. It includes a reflection-free,
+// zero-allocation JSON encoder, and the base Logger strives to avoid
+// serialization overhead and allocations wherever possible. By building the
+// high-level SugaredLogger on that foundation, zap lets users choose when
+// they need to count every allocation and when they'd prefer a more familiar,
+// loosely typed API.
+//
+// Choosing a Logger
+//
+// In contexts where performance is nice, but not critical, use the
+// SugaredLogger. It's 4-10x faster than other structured logging packages and
+// supports both structured and printf-style logging. Like log15 and go-kit,
+// the SugaredLogger's structured logging APIs are loosely typed and accept a
+// variadic number of key-value pairs. (For more advanced use cases, they also
+// accept strongly typed fields - see the SugaredLogger.With documentation for
+// details.)
+//  sugar := zap.NewExample().Sugar()
+//  defer sugar.Sync()
+//  sugar.Infow("failed to fetch URL",
+//    "url", "http://example.com",
+//    "attempt", 3,
+//    "backoff", time.Second,
+//  )
+//  sugar.Infof("failed to fetch URL: %s", "http://example.com")
+//
+// By default, loggers are unbuffered. However, since zap's low-level APIs
+// allow buffering, calling Sync before letting your process exit is a good
+// habit.
+//
+// In the rare contexts where every microsecond and every allocation matter,
+// use the Logger. It's even faster than the SugaredLogger and allocates far
+// less, but it only supports strongly-typed, structured logging.
+//  logger := zap.NewExample()
+//  defer logger.Sync()
+//  logger.Info("failed to fetch URL",
+//    zap.String("url", "http://example.com"),
+//    zap.Int("attempt", 3),
+//    zap.Duration("backoff", time.Second),
+//  )
+//
+// Choosing between the Logger and SugaredLogger doesn't need to be an
+// application-wide decision: converting between the two is simple and
+// inexpensive.
+//   logger := zap.NewExample()
+//   defer logger.Sync()
+//   sugar := logger.Sugar()
+//   plain := sugar.Desugar()
+//
+// Configuring Zap
+//
+// The simplest way to build a Logger is to use zap's opinionated presets:
+// NewExample, NewProduction, and NewDevelopment. These presets build a logger
+// with a single function call:
+//  logger, err := zap.NewProduction()
+//  if err != nil {
+//    log.Fatalf("can't initialize zap logger: %v", err)
+//  }
+//  defer logger.Sync()
+//
+// Presets are fine for small projects, but larger projects and organizations
+// naturally require a bit more customization. For most users, zap's Config
+// struct strikes the right balance between flexibility and convenience. See
+// the package-level BasicConfiguration example for sample code.
+//
+// More unusual configurations (splitting output between files, sending logs
+// to a message queue, etc.) are possible, but require direct use of
+// go.uber.org/zap/zapcore. See the package-level AdvancedConfiguration
+// example for sample code.
+//
+// Extending Zap
+//
+// The zap package itself is a relatively thin wrapper around the interfaces
+// in go.uber.org/zap/zapcore. Extending zap to support a new encoding (e.g.,
+// BSON), a new log sink (e.g., Kafka), or something more exotic (perhaps an
+// exception aggregation service, like Sentry or Rollbar) typically requires
+// implementing the zapcore.Encoder, zapcore.WriteSyncer, or zapcore.Core
+// interfaces. See the zapcore documentation for details.
+//
+// Similarly, package authors can use the high-performance Encoder and Core
+// implementations in the zapcore package to build their own loggers.
+//
+// Frequently Asked Questions
+//
+// An FAQ covering everything from installation errors to design decisions is
+// available at https://github.com/uber-go/zap/blob/master/FAQ.md.
+package zap // import "go.uber.org/zap"