Struct semver::VersionReq

source · [−]

pub struct VersionReq { /* private fields */ }

Expand description

A VersionReq is a struct containing a list of predicates that can apply to ranges of version numbers. Matching operations can then be done with the VersionReq against a particular version to see if it satisfies some or all of the constraints.

Implementations

source

impl VersionReq

source

pub fn any() -> VersionReq

any() is a factory method which creates a VersionReq with no constraints. In other words, any version will match against it.

Examples

use semver::VersionReq;

let anything = VersionReq::any();

source

pub fn parse(input: &str) -> Result<VersionReq, ReqParseError>

parse() is the main constructor of a VersionReq. It takes a string like "^1.2.3" and turns it into a VersionReq that matches that particular constraint.

A Result is returned which contains a ReqParseError if there was a problem parsing the VersionReq. ReqParseError: enum.ReqParseError.html

Examples

use semver::VersionReq;

let version = VersionReq::parse("=1.2.3");
let version = VersionReq::parse(">1.2.3");
let version = VersionReq::parse("<1.2.3");
let version = VersionReq::parse("~1.2.3");
let version = VersionReq::parse("^1.2.3");
let version = VersionReq::parse("1.2.3"); // synonym for ^1.2.3
let version = VersionReq::parse("<=1.2.3");
let version = VersionReq::parse(">=1.2.3");

This example demonstrates error handling, and will panic.

use semver::VersionReq;

let version = match VersionReq::parse("not a version") {
    Ok(version) => version,
    Err(e) => panic!("There was a problem parsing: {}", e),
};

Errors

Returns an error variant if the input could not be parsed as a semver requirement.

Examples of common error causes are as follows:

\0 - an invalid version requirement is used.
>= >= 1.2.3 - multiple operations are used. Only use one.
>== 1.2.3 - an invalid operation is used.
a.0.0 - version components are not numeric.
1.2.3- - an invalid identifier is present.
>= - major version was not specified. At least a major version is required.
0.2* - deprecated requirement syntax. Equivalent would be 0.2.*.

You may also encounter an UnimplementedVersionRequirement error, which indicates that a given requirement syntax is not yet implemented in this crate.

source

pub fn exact(version: &Version) -> VersionReq

exact() is a factory method which creates a VersionReq with one exact constraint.

Examples

use semver::VersionReq;
use semver::Version;

let version = Version { major: 1, minor: 1, patch: 1, pre: vec![], build: vec![] };
let exact = VersionReq::exact(&version);

source

pub fn matches(&self, version: &Version) -> bool

matches() matches a given Version against this VersionReq. Version: struct.Version.html

Examples

use semver::VersionReq;
use semver::Version;

let version = Version { major: 1, minor: 1, patch: 1, pre: vec![], build: vec![] };
let exact = VersionReq::exact(&version);

assert!(exact.matches(&version));

source

pub fn is_exact(&self) -> bool

is_exact() returns true if there is exactly one version which could match this VersionReq. If false is returned, it is possible that there may still only be exactly one version which could match this VersionReq. This function is intended do allow short-circuiting more complex logic where being able to handle only the possibility of a single exact version may be cheaper.

Examples

use semver::ReqParseError;
use semver::VersionReq;

fn use_is_exact() -> Result<(), ReqParseError> {
  assert!(VersionReq::parse("=1.0.0")?.is_exact());
  assert!(!VersionReq::parse("=1.0")?.is_exact());
  assert!(!VersionReq::parse(">=1.0.0")?.is_exact());
  Ok(())
}

use_is_exact().unwrap();