chore: clarify NON_EXISTENT replacement

Co-authored-by: Bjorn Lu <bjornlu.dev@gmail.com>
vitejs · Mar 7, 2023 · 0d82ad1 · 0d82ad1
1 parent 8e78658
commit 0d82ad1
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/docs/guide/env-and-mode.md b/docs/guide/env-and-mode.md
@@ -116,6 +116,8 @@ Vite also supports replacing env variables in HTML files. Any properties in `imp
 <p>Using data from %VITE_API_URL%</p>
 ```
 
+If the env doesn't exist in `import.meta.env`, e.g. `%NON_EXISTENT%`, it will be ignored and not replaced,  unlike `import.meta.env.NON_EXISTENT` in JS where it's replaced as `undefined`.
+
 ## Modes
 
 By default, the dev server (`dev` command) runs in `development` mode and the `build` command runs in `production` mode.