Merge pull request kcl-lang#32 from zong-zhe/add-details-readme

feat: add how to set env in README.

README-zh.md

@@ -72,6 +72,23 @@ GLOBAL OPTIONS:
    --version, -v  print the version
 ```
 
+### 设置环境变量
+
+你需要设置一个环境变量 KPM_HOME 来声明 `kpm` 下载的 KCL 包的位置。
+
+注意: 目前 `kpm` 不支持将外部的包下载到包的内部，所以请确保 `$KPM_HOME` 目录下没有 `kcl.mod` 文件。
+
+```shell
+# Kpm 下载的包将会保存在 /user/xxx/xxx/path 目录下. 
+export KPM_HOME="/user/xxx/xxx/path" 
+```
+
+在成功安装 KCLVM 后，为了确保 KCLVM 可以找到 `kpm` 下载的包，你需要设置环境变量 $KCLVM_VENDOR_HOME 并将其指向 $KPM_HOME。
+
+```shell
+export KCLVM_VENDOR_HOME=$KPM_HOME
+```
+
 ## 快速开始
 
 ### 初始化一个空的 KCL 包

README.md

@@ -72,6 +72,23 @@ GLOBAL OPTIONS:
    --version, -v  print the version
 ```
 
+### Set environment variables
+
+You need to set an environment variable `KPM_HOME` to hold the KCL packages downloaded by `kpm`.
+
+Note: `kpm` does not support downloading external packages into the current kcl package directory, so make sure there is no `kcl.mod` file in the $KPM_HOME directory.
+
+```shell
+# The directory to save the packages downloaded by Kpm. 
+export KPM_HOME="/user/xxx/xxx/path" 
+```
+
+To ensure that KCLVM can find the packages downloaded by `kpm`, you need to set the environment variables `$KCLVM_VENDOR_HOME` and point it to `$KPM_HOME` for KCLVM after downloading KCLVM.
+
+```shell
+export KCLVM_VENDOR_HOME=$KPM_HOME
+```
+
 ## Quick Start
 
 ### Init an empty kcl package