Version — Elixir v1.18.3 (original) (raw)
Functions for parsing and matching versions against requirements.
A version is a string in a specific format or a Versiongenerated after parsing via Version.parse/1.
Although Elixir projects are not required to follow SemVer, they must follow the format outlined on SemVer 2.0 schema.
Versions
In a nutshell, a version is represented by three numbers:
MAJOR.MINOR.PATCH
Pre-releases are supported by optionally appending a hyphen and a series of period-separated identifiers immediately following the patch version. Identifiers consist of only ASCII alphanumeric characters and hyphens ([0-9A-Za-z-]
):
"1.0.0-alpha.3"
Build information can be added by appending a plus sign and a series of dot-separated identifiers immediately following the patch or pre-release version. Identifiers consist of only ASCII alphanumeric characters and hyphens ([0-9A-Za-z-]
):
"1.0.0-alpha.3+20130417140000.amd64"
Requirements
Requirements allow you to specify which versions of a given dependency you are willing to work against. Requirements support the common comparison operators such as >
, >=
, <
, <=
, and ==
that work as one would expect, and additionally the special operator ~>
described in detail further below.
# Only version 2.0.0
"== 2.0.0"
# Anything later than 2.0.0
"> 2.0.0"
Requirements also support and
and or
for complex conditions:
# 2.0.0 and later until 2.1.0
">= 2.0.0 and < 2.1.0"
Since the example above is such a common requirement, it can be expressed as:
"~> 2.0.0"
~>
will never include pre-release versions of its upper bound, regardless of the usage of the :allow_pre
option, or whether the operand is a pre-release version. It can also be used to set an upper bound on only the major version part. See the table below for ~>
requirements and their corresponding translations.
~> | Translation |
---|---|
~> 2.0.0 | >= 2.0.0 and < 2.1.0 |
~> 2.1.2 | >= 2.1.2 and < 2.2.0 |
~> 2.1.3-dev | >= 2.1.3-dev and < 2.2.0 |
~> 2.0 | >= 2.0.0 and < 3.0.0 |
~> 2.1 | >= 2.1.0 and < 3.0.0 |
The requirement operand after the ~>
is allowed to omit the patch version, allowing us to express ~> 2.1
or ~> 2.1-dev
, something that wouldn't be allowed when using the common comparison operators.
When the :allow_pre
option is set false
in Version.match?/3, the requirement will not match a pre-release version unless the operand is a pre-release version. The default is to always allow pre-releases but note that in Hex :allow_pre
is set to false
. See the table below for examples.
Requirement | Version | :allow_pre | Matches |
---|---|---|---|
~> 2.0 | 2.1.0 | true or false | true |
~> 2.0 | 3.0.0 | true or false | false |
~> 2.0.0 | 2.0.5 | true or false | true |
~> 2.0.0 | 2.1.0 | true or false | false |
~> 2.1.2 | 2.1.6-dev | true | true |
~> 2.1.2 | 2.1.6-dev | false | false |
~> 2.1-dev | 2.2.0-dev | true or false | true |
~> 2.1.2-dev | 2.1.6-dev | true or false | true |
>= 2.1.0 | 2.2.0-dev | true | true |
>= 2.1.0 | 2.2.0-dev | false | false |
>= 2.1.0-dev | 2.2.6-dev | true or false | true |
Summary
Functions
Compiles a requirement to an internal representation that may optimize matching.
Checks if the given version matches the specification.
Parses a version string into a Version struct.
Parses a version string into a Version.
Converts the given version to a string.
Types
@type t() :: %Version{ build: build(), major: major(), minor: minor(), patch: patch(), pre: pre() }
Functions
The Version struct.
It contains the fields :major
, :minor
, :patch
, :pre
, and:build
according to SemVer 2.0, where :pre
is a list.
You can read those fields but you should not create a new Versiondirectly via the struct syntax. Instead use the functions in this module.
@spec compare(version(), version()) :: :gt | :eq | :lt
Compares two versions.
Returns :gt
if the first version is greater than the second one, and :lt
for vice versa. If the two versions are equal, :eq
is returned.
Pre-releases are strictly less than their corresponding release versions.
Patch segments are compared lexicographically if they are alphanumeric, and numerically otherwise.
Build segments are ignored: if two versions differ only in their build segment they are considered to be equal.
Raises a Version.InvalidVersionError exception if any of the two given versions are not parsable. If given an already parsed version this function won't raise.
Examples
iex> Version.compare("2.0.1-alpha1", "2.0.0")
:gt
iex> Version.compare("1.0.0-beta", "1.0.0-rc1")
:lt
iex> Version.compare("1.0.0-10", "1.0.0-2")
:gt
iex> Version.compare("2.0.1+build0", "2.0.1")
:eq
iex> Version.compare("invalid", "2.0.1")
** (Version.InvalidVersionError) invalid version: "invalid"
Compiles a requirement to an internal representation that may optimize matching.
The internal representation is opaque.
Checks if the given version matches the specification.
Returns true
if version
satisfies requirement
, false
otherwise. Raises a Version.InvalidRequirementError exception if requirement
is not parsable, or a Version.InvalidVersionError exception if version
is not parsable. If given an already parsed version and requirement this function won't raise.
Options
:allow_pre
(boolean) - whenfalse
, pre-release versions will not match unless the operand is a pre-release version. Defaults totrue
. For examples, please refer to the table above under the "Requirements" section.
Examples
iex> Version.match?("2.0.0", "> 1.0.0")
true
iex> Version.match?("2.0.0", "== 1.0.0")
false
iex> Version.match?("2.1.6-dev", "~> 2.1.2")
true
iex> Version.match?("2.1.6-dev", "~> 2.1.2", allow_pre: false)
false
iex> Version.match?("foo", "== 1.0.0")
** (Version.InvalidVersionError) invalid version: "foo"
iex> Version.match?("2.0.0", "== == 1.0.0")
** (Version.InvalidRequirementError) invalid requirement: "== == 1.0.0"
@spec parse(String.t()) :: {:ok, t()} | :error
Parses a version string into a Version struct.
Examples
iex> Version.parse("2.0.1-alpha1")
{:ok, %Version{major: 2, minor: 0, patch: 1, pre: ["alpha1"]}}
iex> Version.parse("2.0-alpha1")
:error
Parses a version string into a Version.
If string
is an invalid version, a Version.InvalidVersionError is raised.
Examples
iex> Version.parse!("2.0.1-alpha1")
%Version{major: 2, minor: 0, patch: 1, pre: ["alpha1"]}
iex> Version.parse!("2.0-alpha1")
** (Version.InvalidVersionError) invalid version: "2.0-alpha1"
Parses a version requirement string into a Version.Requirement struct.
Examples
iex> {:ok, requirement} = Version.parse_requirement("== 2.0.1")
iex> requirement
Version.parse_requirement!("== 2.0.1")
iex> Version.parse_requirement("== == 2.0.1")
:error
Parses a version requirement string into a Version.Requirement struct.
If string
is an invalid requirement, a Version.InvalidRequirementError is raised.
Examples
iex> Version.parse_requirement!("== 2.0.1")
Version.parse_requirement!("== 2.0.1")
iex> Version.parse_requirement!("== == 2.0.1")
** (Version.InvalidRequirementError) invalid requirement: "== == 2.0.1"
Converts the given version to a string.
Examples
iex> Version.to_string(%Version{major: 1, minor: 2, patch: 3})
"1.2.3"
iex> Version.to_string(Version.parse!("1.14.0-rc.0+build0"))
"1.14.0-rc.0+build0"