Function version_check::is_feature_flaggable [−][src]
Expand description
Checks whether the running or installed rustc
supports feature flags.
In other words, if the channel is either “nightly” or “dev”.
Note that support for specific rustc
features can be enabled or disabled
via the allow-features
compiler flag, which this function does not
check. That is, this function does not check whether a specific feature
is supported, but instead whether features are supported at all. To check
for support for a specific feature, use supports_feature()
.
If the version could not be determined, returns None
. Otherwise returns
true
if the running version supports feature flags and false
otherwise.