pub const IF_NONE_MATCH: OptNumber;
Expand description
If-None-Match
generated from RFC7252 section 5.10.8.2
The If-None-Match Option MAY be used to make a request conditional on the nonexistence of the target resource. If-None-Match is useful for resource creation requests, such as PUT requests, as a means for protecting against accidental overwrites when multiple clients are acting in parallel on the same resource. The If-None-Match Option carries no value.
If the target resource does exist, then the condition is not fulfilled.
(It is not very useful to combine If-Match and If-None-Match options in one request, because the condition will then never be fulfilled.)