Commit b003539a authored by Jay Conrod's avatar Jay Conrod

doc: add sections for modules, packages, versions to module reference

Updates #33637

Change-Id: I3a0d05551d5a680febf742b912a5a6e5af753a6e
Reviewed-on: https://go-review.googlesource.com/c/go/+/206617
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: default avatarTyler Bui-Palsulich <tbp@google.com>
parent 8b1e8a42
......@@ -13,9 +13,81 @@ this document to HTML before Go 1.14. -->
<a id="modules-overview"></a>
## Modules, packages, and versions
A [*module*](#glos-module) is a collection of packages that are released,
versioned, and distributed together. A module is identified by a [*module
path*](#glos-module-path), which is declared in a [`go.mod`
file](#go.mod-files), together with information about the module's
dependencies. The [*module root directory*](#glos-module-root-directory) is the
directory that contains the `go.mod` file. The [*main
module*](#glos-main-module) is the module containing the directory where the
`go` command is invoked.
Each [*package*](#glos-package) within a module is a collection of source files
in the same directory that are compiled together. A [*package
path*](#glos-package-path) is the module path joined with the subdirectory
containing the package (relative to the module root). For example, the module
`"golang.org/x/net"` contains a package in the directory `"html"`. That
package's path is `"golang.org/x/net/html"`.
<a id="versions"></a>
### Versions
A [*version*](#glos-version) identifies an immutable snapshot of a module, which
may be either a [release](#glos-release-version) or a
[pre-release](#glos-pre-release-version). Each version starts with the letter
`v`, followed by a semantic version. See [Semantic Versioning
2.0.0](https://semver.org/spec/v2.0.0.html) for details on how versions are
formatted, interpreted, and compared.
To summarize, a semantic version consists of three non-negative integers (the
major, minor, and patch versions, from left to right) separated by dots. The
patch version may be followed by an optional pre-release string starting with a
hyphen. The pre-release string or patch version may be followed by a build
metadata string starting with a plus. For example, `v0.0.0`, `v1.12.134`,
`v8.0.5-pre`, and `v2.0.9+meta` are valid versions.
Each part of a version indicates whether the version is stable and whether it is
compatible with previous versions.
* The [major version](#glos-major-version) must be incremented and the minor
and patch versions must be set to zero after a backwards incompatible change
is made to the module's public interface or documented functionality, for
example, after a package is removed.
* The [minor version](#glos-minor-version) must be incremented and the patch
version set to zero after a backwards compatible change, for example, after a
new function is added.
* The [patch version](#glos-patch-version) must be incremented after a change
that does not affect the module's public interface, such as a bug fix or
optimization.
* The pre-release suffix indicates a version is a
[pre-release](#glos-pre-release-version). Pre-release versions sort before
the corresponding release versions. For example, `v1.2.3-pre` comes before
`v1.2.3`.
* The build metadata suffix is ignored for the purpose of comparing versions.
Tags with build metadata are ignored in version control repositories, but
build metadata is preserved in versions specified in `go.mod` files. The
suffix `+incompatible` denotes a version released before migrating to modules
version major version 2 or later (see [Compatibility with non-module
repositories](#non-module-compat).
A version is considered unstable if its major version is 0 or it has a
pre-release suffix. Unstable versions are not subject to compatibility
requirements. For example, `v0.2.0` may not be compatible with `v0.1.0`, and
`v1.5.0-beta` may not be compatible with `v1.5.0`.
Go may access modules in version control systems using tags, branches, or
revisions that don't follow these conventions. However, within the main module,
the `go` command will automatically convert revision names that don't follow
this standard into canonical versions. The `go` command will also remove build
metadata suffixes (except for `+incompatible`) as part of this process. This may
result in a [*pseudo-version*](#glos-pseudo-version), a pre-release version that
encodes a revision identifier (such as a Git commit hash) and a timestamp from a
version control system. For example, the command `go get -d
golang.org/x/net@daa7c041` will convert the commit hash `daa7c041` into the
pseudo-version `v0.0.0-20191109021931-daa7c04131f5`. Canonical versions are
required outside the main module, and the `go` command will report an error if a
non-canonical version like `master` appears in a `go.mod` file.
<a id="major-version-suffixes"></a>
### Major version suffixes
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment