pub fn version_req(mut self, version_req: &str) -> Self {
        self.version_req = u::EncodableCrateVersionReq(
            semver::VersionReq::parse(version_req)
                .expect("version req isn't a valid semver::VersionReq"),
        );
        self
    }
/// Set the version requirement for this dependency.
///
/// # Panics
///
/// Panics if the `version_req` string specified isn't a valid `semver::VersionReq`.
Set the version requirement for this dependency.
Set the version requirement for this dependency .
pub fn version_req(mut self, version_req: &str) -> Self {
        self.version_req = u::EncodableCrateVersionReq(
            semver::VersionReq::parse(version_req)
                .expect("version req isn't a valid semver::VersionReq"),
        );
        self
    }
pub fn version_req ( mut self , version_req : & str ) -> Self { self . version_req = u :: EncodableCrateVersionReq ( semver :: VersionReq :: parse ( version_req ) . expect ( " " ) , ) ; self }
Set the version requirement for this dependency.
Set the version requirement for this dependency .
mut self
version_req
&str
panics
Panics if the `version_req` string specified isn't a valid `semver::VersionReq`.
Panics if the ` version_req ` string specified isn ' t a valid ` semver :: VersionReq ` .