Erlang Rebar 使用指南之四：依赖管理
全文目录：
https://github.com/rebar/rebar/wiki
本章链接：
https://github.com/rebar/rebar/wiki/Dependency-management
1 rebar依赖定义
Rebar取得和构建符合OTP/Rebar规范的项目。如果项目包含子项目，Rebar会自动递归地构建它们。
项目的依赖在project_dir/rebar.config中定义，形式如下：
{deps,[Dependency1,Dependency2,...]}.
其中每一项(Dependency?)都按照{
App,VsnRegex,Source,[raw]}定义：
- 'App' 指定OTP应用名称，可以是atom或字符串
- 'VsnRegex' 用于匹配版本号的正则表达式
- 'Source' 按照下面的格式指定OTP应用的地址:
{hg,Url,Rev} Fetch from mercury repository
{git,Url} Fetch from git repository
{git,{branch,Branch}} Fetch from git repository
{git,""} == {git,"HEAD"}} Fetch from git repository
{git,{tag,Tag}} Fetch from git repository
{git,Rev} Fetch from git repository
{bzr,Rev} Fetch from a bazaar repository
[raw]是可选的。包含[raw]的依赖项不要求安装Erlang/OTP的项目结构。项目编译时，该依赖项不会自动被编译，但是下面的命令对其有作用：
get-deps update-deps check-deps list-deps delete-deps
2 rebar.config的例子
{deps,[
{em,".*",{git,"https://github.com/sheyll/erlymock.git"}},{nano_trace,"https://github.com/sheyll/nano_trace.git","feature/rebar-migration"}}},{mochiweb,"2.3.2","https://github.com/mochi/mochiweb.git","v2.3.2"}}},% Or specify a revision to refer a particular commit,useful if the project has only the master branch
% {mochiweb,"15bc558d8222b011e2588efbd86c01d68ad73e60"},% An example of a "raw" dependency:
{rebar,"git://github.com/rebar/rebar.git","master"}},[raw]}
]}.