README
¶
You Don't Know Go Yet Book
Go programming language study notes turned book.
You can read the book online here entirely for FREE.
This book is inspired by 'You Don't Know JS Yet' (YDKJS) book series. YDKJS helped me understand JavaScript under the hood, after more than 8 years writing software in JS.
You Don't Know Go (YDKGo) book is based on Ultimate Go training, which is an intermediate-level class for engineers with some experience with Go trying to dig deeper into the language.
Development
The site is built using the Hugo static site generator. Check out the Hugo Quick Start for a quick intro.
Requirements
- Hugo 0.68 and above
- Hugo extended version (with Sass/SCSS support)
Serving the site locally
To build and locally serve this site, you need to install Hugo, extended version. Once Hugo is installed:
# first, fill Git submodules
make setup
# start Hugo server
make serve
Publishing the site
The website is automatically published by Netlify. Any time changes are pushed to the master branch, the site is rebuilt and redeployed.
Site content
All of the Markdown content used to build the site's documentation is in the content directory.
Expand License
This repository contains a variety of content; some developed by Cedric Chee, and some from third-parties. The third-party content is distributed under the license provided by those parties.
The content of this project itself is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License, and the underlying source code used to format and display that content is licensed under the Apache License, Version 2.0.
The Go gopher was designed by Renee French, is licensed under Creative Commons 3.0 Attributions.
Gopher picture by Maria Letta.
Directories
¶
| Path | Synopsis |
|---|---|
|
content
|
|
|
docs/concurrency/channels/advanced/example1
Sample program to show the order of channel communication for unbuffered, buffered and closing channels based on the specification.
|
Sample program to show the order of channel communication for unbuffered, buffered and closing channels based on the specification. |
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docs/concurrency/channels/example1
This sample program demonstrates the basic channel mechanics for goroutine signaling.
|
This sample program demonstrates the basic channel mechanics for goroutine signaling. |
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docs/concurrency/channels/example2
Sample program to show how to use an unbuffered channel to simulate a game of tennis between two goroutines.
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Sample program to show how to use an unbuffered channel to simulate a game of tennis between two goroutines. |
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docs/concurrency/channels/example3
Sample program to show how to use an unbuffered channel to simulate a relay race between four goroutines.
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Sample program to show how to use an unbuffered channel to simulate a relay race between four goroutines. |
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docs/concurrency/channels/example4
This sample program demonstrates how to use a buffered channel to receive results from other goroutines in a guaranteed way.
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This sample program demonstrates how to use a buffered channel to receive results from other goroutines in a guaranteed way. |
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docs/concurrency/channels/example5
This sample program demonstrates how to use a channel to monitor the amount of time the program is running and terminate the program if it runs too long.
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This sample program demonstrates how to use a channel to monitor the amount of time the program is running and terminate the program if it runs too long. |
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docs/concurrency/channels/exercises/exercise1
Write a program where two goroutines pass an integer back and forth ten times.
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Write a program where two goroutines pass an integer back and forth ten times. |
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docs/concurrency/channels/exercises/exercise2
Write a program that uses a fan out pattern to generate 100 random numbers concurrently.
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Write a program that uses a fan out pattern to generate 100 random numbers concurrently. |
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docs/concurrency/channels/exercises/exercise3
Write a program that uses goroutines to generate up to 100 random numbers.
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Write a program that uses goroutines to generate up to 100 random numbers. |
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docs/concurrency/channels/exercises/exercise4
Write a program that creates a fixed set of workers to generate random numbers.
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Write a program that creates a fixed set of workers to generate random numbers. |
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docs/concurrency/context/example1
Sample program to show how to store and retrieve values from a context.
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Sample program to show how to store and retrieve values from a context. |
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docs/concurrency/context/example2
Sample program to show how to use the WithCancel function.
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Sample program to show how to use the WithCancel function. |
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docs/concurrency/context/example3
Sample program to show how to use the WithDeadline function.
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Sample program to show how to use the WithDeadline function. |
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docs/concurrency/context/example4
Sample program to show how to use the WithTimeout function of the Context package.
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Sample program to show how to use the WithTimeout function of the Context package. |
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docs/concurrency/context/example5
Sample program that implements a web request with a context that is used to timeout the request if it takes too long.
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Sample program that implements a web request with a context that is used to timeout the request if it takes too long. |
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docs/concurrency/context/example6
Sample program to show when a Context is canceled, all Contexts derived from it are also canceled.
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Sample program to show when a Context is canceled, all Contexts derived from it are also canceled. |
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docs/concurrency/context/exercise1
Use the template and follow the directions.
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Use the template and follow the directions. |
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docs/concurrency/data_race/advanced/example1
Sample program to show a more complicated race condition using an interface value.
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Sample program to show a more complicated race condition using an interface value. |
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docs/concurrency/data_race/example1
Sample program to show how to create race conditions in our programs.
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Sample program to show how to create race conditions in our programs. |
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docs/concurrency/data_race/example2
Sample program to show how to use the atomic package to provide safe access to numeric types.
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Sample program to show how to use the atomic package to provide safe access to numeric types. |
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docs/concurrency/data_race/example3
Sample program to show how to use a mutex to define critical sections of code that need synchronous access.
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Sample program to show how to use a mutex to define critical sections of code that need synchronous access. |
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docs/concurrency/data_race/example4
Sample program to show how to use a read/write mutex to define critical sections of code that needs synchronous access.
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Sample program to show how to use a read/write mutex to define critical sections of code that needs synchronous access. |
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docs/concurrency/data_race/example5
Sample program to show how maps are not safe for concurrent use by default.
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Sample program to show how maps are not safe for concurrent use by default. |
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docs/concurrency/data_race/exercise1
Fix the race condition in this program.
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Fix the race condition in this program. |
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docs/concurrency/goroutines/example1
Sample program to show how to create goroutines and how the scheduler behaves.
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Sample program to show how to create goroutines and how the scheduler behaves. |
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docs/concurrency/goroutines/example2
Sample program to show how the goroutine scheduler will time slice goroutines on a single thread.
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Sample program to show how the goroutine scheduler will time slice goroutines on a single thread. |
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docs/concurrency/goroutines/example3
Sample program to show how to create goroutines and how the goroutine scheduler behaves with two contexts.
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Sample program to show how to create goroutines and how the goroutine scheduler behaves with two contexts. |
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docs/concurrency/goroutines/exercise1
Create a program that declares two anonymous functions.
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Create a program that declares two anonymous functions. |
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docs/concurrency/patterns/advanced
This sample program demonstrates how the logger package works.
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This sample program demonstrates how the logger package works. |
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docs/design/composition/assertions/example1
Sample program demonstrating when implicit interface conversions are provided by the compiler.
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Sample program demonstrating when implicit interface conversions are provided by the compiler. |
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docs/design/composition/assertions/example2
Sample program demonstrating that type assertions are a runtime and not compile time construct.
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Sample program demonstrating that type assertions are a runtime and not compile time construct. |
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docs/design/composition/assertions/example3
Sample program to show how method sets can affect behavior.
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Sample program to show how method sets can affect behavior. |
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docs/design/composition/decoupling/example1
Sample program demonstrating struct composition.
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Sample program demonstrating struct composition. |
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docs/design/composition/decoupling/example2
Sample program demonstrating decoupling with interfaces.
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Sample program demonstrating decoupling with interfaces. |
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docs/design/composition/decoupling/example3
Sample program demonstrating interface composition.
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Sample program demonstrating interface composition. |
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docs/design/composition/decoupling/example4
Sample program demonstrating decoupling with interface composition.
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Sample program demonstrating decoupling with interface composition. |
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docs/design/composition/decoupling/example5
Sample program demonstrating removing interface pollution.
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Sample program demonstrating removing interface pollution. |
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docs/design/composition/decoupling/example6
Sample program demonstrating being more precise with API design.
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Sample program demonstrating being more precise with API design. |
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docs/design/composition/exercises/exercise1
Using the template, declare a set of concrete types that implement the set of predefined interface types.
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Using the template, declare a set of concrete types that implement the set of predefined interface types. |
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docs/design/composition/grouping/example1
This is an example of using type hierarchies with a OOP pattern.
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This is an example of using type hierarchies with a OOP pattern. |
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docs/design/composition/grouping/example2
This is an example of using composition and interfaces.
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This is an example of using composition and interfaces. |
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docs/design/composition/mocking/example1
Sample program to show how you can personally mock concrete types when you need to for your own packages or tests.
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Sample program to show how you can personally mock concrete types when you need to for your own packages or tests. |
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docs/design/composition/mocking/example1/pubsub
Package pubsub simulates a package that provides publication/subscription type services.
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Package pubsub simulates a package that provides publication/subscription type services. |
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docs/design/composition/pollution/example1
This is an example that creates interface pollution by improperly using an interface when one is not needed.
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This is an example that creates interface pollution by improperly using an interface when one is not needed. |
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docs/design/composition/pollution/example2
This is an example that removes the interface pollution by removing the interface and using the concrete type directly.
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This is an example that removes the interface pollution by removing the interface and using the concrete type directly. |
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docs/design/error_handling/example1
Sample program to show how the default error type is implemented.
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Sample program to show how the default error type is implemented. |
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docs/design/error_handling/example2
Sample program to show how to use error variables to help the caller determine the exact error being returned.
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Sample program to show how to use error variables to help the caller determine the exact error being returned. |
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docs/design/error_handling/example3
http://golang.org/src/pkg/encoding/json/decode.go Sample program to show how to implement a custom error type based on the json package in the standard library.
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http://golang.org/src/pkg/encoding/json/decode.go Sample program to show how to implement a custom error type based on the json package in the standard library. |
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docs/design/error_handling/example4
Package example4 provides code to show how to implement behavior as context.
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Package example4 provides code to show how to implement behavior as context. |
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docs/design/error_handling/example5
Sample program to show see if the class can find the bug.
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Sample program to show see if the class can find the bug. |
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docs/design/error_handling/example5/reason
Sample program to show see if the class can find the bug.
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Sample program to show see if the class can find the bug. |
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docs/design/error_handling/example6
Sample program to show how wrapping errors work.
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Sample program to show how wrapping errors work. |
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docs/design/error_handling/exercise1
Create two error variables, one called ErrInvalidValue and the other called ErrAmountTooLarge.
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Create two error variables, one called ErrInvalidValue and the other called ErrAmountTooLarge. |
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docs/design/error_handling/exercise2
Create a custom error type called appError that contains three fields, err error, message string and code int.
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Create a custom error type called appError that contains three fields, err error, message string and code int. |
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docs/language/arrays/benchmarks/caching
Package caching provides code to show why Data Oriented Design matters.
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Package caching provides code to show why Data Oriented Design matters. |
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docs/language/arrays/example1
Sample program to show how to declare and iterate over arrays of different types.
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Sample program to show how to declare and iterate over arrays of different types. |
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docs/language/arrays/example2
Sample program to show how arrays of different sizes are not of the same type.
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Sample program to show how arrays of different sizes are not of the same type. |
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docs/language/arrays/example3
Sample program to show how the behavior of the for range and how memory for an array is contiguous.
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Sample program to show how the behavior of the for range and how memory for an array is contiguous. |
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docs/language/arrays/example4
Sample program to show how the for range has both value and pointer semantics.
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Sample program to show how the for range has both value and pointer semantics. |
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docs/language/arrays/exercise1
Declare an array of 5 strings with each element initialized to its zero value.
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Declare an array of 5 strings with each element initialized to its zero value. |
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docs/language/constants/example1
Sample program to show how to declare constants and their implementation in Go.
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Sample program to show how to declare constants and their implementation in Go. |
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docs/language/constants/example2
Sample program to show how constants do have a parallel type system.
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Sample program to show how constants do have a parallel type system. |
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docs/language/constants/example3
Sample program to show how iota works.
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Sample program to show how iota works. |
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docs/language/constants/example4
Sample program to show how literal, constant and variables work within the scope of implicit conversion.
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Sample program to show how literal, constant and variables work within the scope of implicit conversion. |
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docs/language/constants/exercise1
Declare an untyped and typed constant and display their values.
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Declare an untyped and typed constant and display their values. |
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docs/language/embedding/example1
Sample program to show how what we are doing is NOT embedding a type but just using a type as a field.
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Sample program to show how what we are doing is NOT embedding a type but just using a type as a field. |
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docs/language/embedding/example2
Sample program to show how to embed a type into another type and the relationship between the inner and outer type.
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Sample program to show how to embed a type into another type and the relationship between the inner and outer type. |
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docs/language/embedding/example3
Sample program to show how embedded types work with interfaces.
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Sample program to show how embedded types work with interfaces. |
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docs/language/embedding/example4
Sample program to show what happens when the outer and inner type implement the same interface.
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Sample program to show what happens when the outer and inner type implement the same interface. |
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docs/language/embedding/exercise1
This program defines a type Feed with two methods: Count and Fetch.
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This program defines a type Feed with two methods: Count and Fetch. |
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docs/language/exporting/example1
Sample program to show how to access an exported identifier.
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Sample program to show how to access an exported identifier. |
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docs/language/exporting/example1/counters
Package counters provides alert counter support.
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Package counters provides alert counter support. |
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docs/language/exporting/example2
Sample program to show how the program can't access an unexported identifier from another package.
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Sample program to show how the program can't access an unexported identifier from another package. |
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docs/language/exporting/example2/counters
Package counters provides alert counter support.
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Package counters provides alert counter support. |
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docs/language/exporting/example3
Sample program to show how the program can access a value of an unexported identifier from another package.
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Sample program to show how the program can access a value of an unexported identifier from another package. |
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docs/language/exporting/example3/counters
Package counters provides alert counter support.
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Package counters provides alert counter support. |
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docs/language/exporting/example4
Sample program to show how unexported fields from an exported struct type can't be accessed directly.
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Sample program to show how unexported fields from an exported struct type can't be accessed directly. |
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docs/language/exporting/example4/users
Package users provides support for user management.
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Package users provides support for user management. |
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docs/language/exporting/example5
Sample program to show how to create values from exported types with embedded unexported types.
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Sample program to show how to create values from exported types with embedded unexported types. |
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docs/language/exporting/example5/users
Package users provides support for user management.
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Package users provides support for user management. |
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docs/language/exporting/exercise1
Create a package named toy with a single exported struct type named Toy.
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Create a package named toy with a single exported struct type named Toy. |
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docs/language/exporting/exercise1/toy
Package toy contains support for managing toy inventory.
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Package toy contains support for managing toy inventory. |
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docs/language/functions/advanced/example1
Sample program to show how to recover from panics.
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Sample program to show how to recover from panics. |
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docs/language/functions/example1
Sample program to show how functions can return multiple values while using named and struct types.
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Sample program to show how functions can return multiple values while using named and struct types. |
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docs/language/functions/example2
Sample program to show how we can use the blank identifier to ignore return values.
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Sample program to show how we can use the blank identifier to ignore return values. |
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docs/language/functions/example3
Sample program to show some of the mechanics behind the short variable declaration operator redeclares.
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Sample program to show some of the mechanics behind the short variable declaration operator redeclares. |
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docs/language/functions/example4
Sample program to show how anonymous functions and closures work.
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Sample program to show how anonymous functions and closures work. |
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docs/language/functions/exercise1
Declare a struct type to maintain information about a user.
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Declare a struct type to maintain information about a user. |
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docs/language/interfaces/advanced/example1
Sample program that explores how interface assignments work when values are stored inside the interface.
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Sample program that explores how interface assignments work when values are stored inside the interface. |
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docs/language/interfaces/example1
Sample program to show how polymorphic behavior with interfaces.
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Sample program to show how polymorphic behavior with interfaces. |
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docs/language/interfaces/example2
Sample program to show how to understand method sets.
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Sample program to show how to understand method sets. |
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docs/language/interfaces/example3
Sample program to show how you can't always get the address of a value.
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Sample program to show how you can't always get the address of a value. |
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docs/language/interfaces/example4
Sample program to show how the concrete value assigned to the interface is what is stored inside the interface.
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Sample program to show how the concrete value assigned to the interface is what is stored inside the interface. |
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docs/language/interfaces/exercise1
Declare an interface named speaker with a method named speak.
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Declare an interface named speaker with a method named speak. |
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docs/language/maps/example1
Sample program to show how to initialize a map, write to it, then read and delete from it.
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Sample program to show how to initialize a map, write to it, then read and delete from it. |
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docs/language/maps/example2
Sample program to show how maps behave when you read an absent key.
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Sample program to show how maps behave when you read an absent key. |
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docs/language/maps/example3
Sample program to show how only types that can have equality defined on them can be a map key.
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Sample program to show how only types that can have equality defined on them can be a map key. |
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docs/language/maps/example4
Sample program to show how to declare, initialize and iterate over a map.
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Sample program to show how to declare, initialize and iterate over a map. |
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docs/language/maps/example5
Sample program to show how to walk through a map by alphabetical key order.
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Sample program to show how to walk through a map by alphabetical key order. |
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docs/language/maps/example6
Sample program to show that you cannot take the address of an element in a map.
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Sample program to show that you cannot take the address of an element in a map. |
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docs/language/maps/example7
Sample program to show how maps are reference types.
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Sample program to show how maps are reference types. |
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docs/language/maps/exercise1
Declare and make a map of integer values with a string as the key.
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Declare and make a map of integer values with a string as the key. |
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docs/language/methods/example1
Sample program to show how to declare methods and how the Go compiler supports them.
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Sample program to show how to declare methods and how the Go compiler supports them. |
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docs/language/methods/example2
Sample program to show how to declare methods against a named type.
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Sample program to show how to declare methods against a named type. |
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docs/language/methods/example3
Sample program to show how to declare function variables.
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Sample program to show how to declare function variables. |
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docs/language/methods/example4
Sample program to show how to declare and use function types.
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Sample program to show how to declare and use function types. |
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docs/language/methods/exercise1
Declare a struct that represents a baseball player.
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Declare a struct that represents a baseball player. |
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docs/language/pointers/example1
Sample program to show the basic concept of pass by value.
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Sample program to show the basic concept of pass by value. |
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docs/language/pointers/example2
Sample program to show the basic concept of using a pointer to share data.
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Sample program to show the basic concept of using a pointer to share data. |
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docs/language/pointers/example3
Sample program to show the basic concept of using a pointer to share data.
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Sample program to show the basic concept of using a pointer to share data. |
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docs/language/pointers/example4
Sample program to teach the mechanics of escape analysis.
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Sample program to teach the mechanics of escape analysis. |
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docs/language/pointers/example5
Sample program to show how stacks grow/change.
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Sample program to show how stacks grow/change. |
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docs/language/pointers/exercise1
Declare and initialize a variable of type int with the value of 20.
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Declare and initialize a variable of type int with the value of 20. |
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docs/language/pointers/exercise2
Declare a struct type and create a value of this type.
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Declare a struct type and create a value of this type. |
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docs/language/slices/example1
Sample program to show how the capacity of the slice is not available for use.
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Sample program to show how the capacity of the slice is not available for use. |
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docs/language/slices/example2
Sample program to show the components of a slice.
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Sample program to show the components of a slice. |
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docs/language/slices/example3
Sample program to show how to takes slices of slices to create different views of and make changes to the underlying array.
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Sample program to show how to takes slices of slices to create different views of and make changes to the underlying array. |
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docs/language/slices/example4
Sample program to show how to grow a slice using the built-in function append and how append grows the capacity of the underlying array.
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Sample program to show how to grow a slice using the built-in function append and how append grows the capacity of the underlying array. |
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docs/language/slices/example5
Sample program to show how one needs to be careful when appending to a slice when you have a reference to an element.
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Sample program to show how one needs to be careful when appending to a slice when you have a reference to an element. |
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docs/language/slices/example6
Sample program to show how strings have a UTF-8 encoded byte array.
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Sample program to show how strings have a UTF-8 encoded byte array. |
|
docs/language/slices/example7
Sample program to show how to declare and use variadic functions.
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Sample program to show how to declare and use variadic functions. |
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docs/language/slices/example8
Sample program to show how the for range has both value and pointer semantics.
|
Sample program to show how the for range has both value and pointer semantics. |
|
docs/language/slices/exercise1
Declare a nil slice of integers.
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Declare a nil slice of integers. |
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docs/language/struct_types/example1
Sample program to show how to declare and initialize struct types.
|
Sample program to show how to declare and initialize struct types. |
|
docs/language/struct_types/example2
Sample program to show how to declare and initialize anonymous struct types.
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Sample program to show how to declare and initialize anonymous struct types. |
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docs/language/struct_types/example3
Sample program to show how variables of an unnamed type can be assigned to variables of a named type, when they are identical.
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Sample program to show how variables of an unnamed type can be assigned to variables of a named type, when they are identical. |
|
docs/language/struct_types/exercise1
Declare a struct type to maintain information about a user (name, email and age).
|
Declare a struct type to maintain information about a user (name, email and age). |
|
docs/language/variables/example1
Sample program to show how to declare variables.
|
Sample program to show how to declare variables. |
|
docs/language/variables/exercise1
Declare three variables that are initialized to their zero value and three declared with a literal value.
|
Declare three variables that are initialized to their zero value and three declared with a literal value. |
|
docs/profiling/bce
Package bce shows a sample function that does not take into consideration the extra bounds checks that the compiler places in code for integrity.
|
Package bce shows a sample function that does not take into consideration the extra bounds checks that the compiler places in code for integrity. |
|
docs/profiling/godebug
Sample program that implements a simple web service that will allow us to explore how to use the GODEBUG variable.
|
Sample program that implements a simple web service that will allow us to explore how to use the GODEBUG variable. |
|
docs/profiling/http_trace/example1
Sample program to show how the httptrace package provides a number of hooks to gather information during an HTTP round trip about a variety of events.
|
Sample program to show how the httptrace package provides a number of hooks to gather information during an HTTP round trip about a variety of events. |
|
docs/profiling/http_trace/example2
Sample program to show how to use the http trace with a unique Client and Transport.
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Sample program to show how to use the http trace with a unique Client and Transport. |
|
docs/profiling/memcpu
Sample program that takes a stream of bytes and looks for the bytes “elvis” and when they are found, replace them with “Elvis”.
|
Sample program that takes a stream of bytes and looks for the bytes “elvis” and when they are found, replace them with “Elvis”. |
|
docs/profiling/pprof
Sample program that implements a simple web service that will allow us to explore how to use the http/pprof tooling.
|
Sample program that implements a simple web service that will allow us to explore how to use the http/pprof tooling. |
|
docs/profiling/project/search
Package search manages the searching of results against different news feeds.
|
Package search manages the searching of results against different news feeds. |
|
docs/profiling/project/service
Package service maintains the logic for the web service.
|
Package service maintains the logic for the web service. |
|
docs/profiling/stack_trace/example1
Sample program to show how to read a stack trace.
|
Sample program to show how to read a stack trace. |
|
docs/profiling/stack_trace/example2
Sample program to show how to read a stack trace when it packs values.
|
Sample program to show how to read a stack trace when it packs values. |
|
docs/profiling/stack_trace/example3
Sample program that implements a simple web service that will allow us to explore how to look at core dumps.
|
Sample program that implements a simple web service that will allow us to explore how to look at core dumps. |
|
docs/profiling/trace
Sample program that performs a series of I/O related tasks to better understand tracing in Go.
|
Sample program that performs a series of I/O related tasks to better understand tracing in Go. |
|
docs/testing/benchmarks/caching
Package caching provides code to show why Data Oriented Design matters.
|
Package caching provides code to show why Data Oriented Design matters. |
|
docs/testing/benchmarks/cpu-bound
Understanding your workload is critically important in understanding if something can be made concurrent and how complex it is to perform.
|
Understanding your workload is critically important in understanding if something can be made concurrent and how complex it is to perform. |
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docs/testing/benchmarks/io-bound
Understanding your workload is critically important in understanding if something can be made concurrent and how complex it is to perform.
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Understanding your workload is critically important in understanding if something can be made concurrent and how complex it is to perform. |
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docs/testing/tests/example4
Sample program that implements a simple web service.
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Sample program that implements a simple web service. |
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docs/testing/tests/example4/handlers
Package handlers provides the endpoints for the web service.
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Package handlers provides the endpoints for the web service. |
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