Skip to content

docs: update Motoko env var example to motoko-core Runtime.envVar #408

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
marc0olo merged 1 commit into from
Mar 5, 2026
+3 −5
Merged

docs: update Motoko env var example to motoko-core Runtime.envVar #408

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
8 changes: 3 additions & 5 deletions docs/concepts/canister-discovery.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -104,20 +104,18 @@ let backend_id = Principal::from_text(
).unwrap();
```

**Motoko** canisters can read canister environment variables using `Prim.envVar` (since Motoko 0.16.2):
**Motoko** canisters can read canister environment variables using `Runtime.envVar` from the [motoko-core](https://mops.one/core) package (v2.1.0+):

```motoko
import Prim "mo:⛔";
import Runtime "mo:core/Runtime";
import Principal "mo:core/Principal";

let ?backendIdText = Prim.envVar<system>("PUBLIC_CANISTER_ID:backend") else {
let ?backendIdText = Runtime.envVar("PUBLIC_CANISTER_ID:backend") else {
return #err("backend canister ID not set");
};
let backendId = Principal.fromText(backendIdText);
```

> **Note:** `Prim` is an internal module not intended for general use. This functionality will be available in the Motoko core package in a future release.

### Making Inter-Canister Calls

Once you have the target canister ID, make calls using your language's CDK:
Expand Down
Loading