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Version: 2.9.x(Latest)

Go 1.18 (2022-03-15)

Go 1.18 was released in March 2022 and is one of the most significant releases in the history of the Go language, introducing Generics, Fuzzing, and Workspaces.

Major Changes​

Language​

  • Generics: Introduced support for parametric polymorphism, allowing functions and data structures to be written for multiple types.
  • Type Parameters: Functions and type declarations now support type parameters.
  • Constraints: Interfaces can now define sets of types to be used as type constraints.
  • any: Added the predefined identifier any as an alias for interface{}.
  • comparable: Added the predefined identifier comparable, representing the set of all comparable types.
  • ~ Operator: Used to represent the underlying type set.
func Min[T constraints.Ordered](x, y T) T {
    if x < y {
        return x
    }
    return y
}

Toolchain​

  • Fuzzing: The go test command now has built-in support for fuzzing to help discover bugs in edge cases.

    go test -fuzz=FuzzMyFunc

  • Workspaces: Introduced go.work files and the go work command, supporting a multi-module workspace development mode. This facilitates simultaneous modification of multiple interdependent modules without modifying go.mod replace directives.

  • go get: go get no longer builds or installs packages (it is now dedicated to managing go.mod dependencies). Use go install to install executables.

  • GOAMD64: Introduced the GOAMD64 environment variable, allowing the selection of the AMD64 architecture microarchitecture level (v1-v4) to leverage newer instruction sets for improved performance.

Performance​

  • Performance Improvements: Significant performance improvements (up to 20%) on Apple M1, ARM64, and PowerPC64 architectures.
  • Compiler: Compilation speed may be slightly slower (about 15%) due to the introduction of generics, but the execution efficiency of the generated code is unaffected.

Standard Library​

  • net/netip: Added net/netip package, defining a new IP address type Addr, which is smaller, more efficient, immutable, and supports being used as a map key compared to net.IP.

  • strings / bytes:

    • Added Cut function to simplify string splitting operations.
    • Added Clone function to copy strings or byte slices.
      before, after, found := strings.Cut("hello,world", ",")

  • debug/buildinfo: Added package for reading build information embedded in Go binaries (module version, VCS info, build flags, etc.).

  • sync: Mutex and RWMutex added TryLock method.

  • tls: TLS 1.0 and 1.1 are disabled by default for clients.

  • crypto/x509: SHA-1 signed certificates are rejected by default.

References​

For more details, please refer to the official release notes: Go 1.18 Release Notes