https://www.dartlang.org/tools/pub/versioning
'^':支持小版本,大版本不包括,The string ^2.3.5
means “the range of all versions from 2.3.5 to 3.0.0, not including 3.0.0.”
'+':表示与上一版有变化,但API接口一致,The interpretation of each number is just shifted down one slot: going from 0.1.2
to 0.2.0
indicates a breaking change, going to 0.1.3
indicates a new feature, and going to 0.1.2+1
indicates a change that doesn’t affect the public API
如果直接用<或>约束,须加上单引号‘’,使用^,可不加引号;If the >
character is in the version constraint, be sure to quote the constraint string, so the character isn’t interpreted as YAML syntax. For example, never use >=1.2.3 <2.0.0
; instead, use '>=1.2.3 <2.0.0'
or ^1.2.3
.
https://www.dartlang.org/tools/pub/dependencies
Semantic Versioning: https://semver.org/spec/v2.0.0-rc.1.html