Polyfill: Initial demo

Closes #10.

polyfill.js

@@ -0,0 +1,36 @@
+// This polyfill of the WinterCG CLI API proposal is highly likely to have breaking changes in the future!
+// https://github.com/CanadaHonk/proposal-cli-api
+
+// Implemented:
+// - args
+
+
+const NAMESPACE = 'CLI';
+
+if (typeof process !== 'undefined') {
+ // Node or Node-compatible runtime (Bun):
+ // process.argv already excludes arguments used by the runtime,
+ // but still has the runtime binary path and script path.
+
+ const { argv } = process;
+ globalThis[NAMESPACE] = {
+ args: argv.slice(2)
+ };
+} else if (typeof Deno !== 'undefined') {
+ // Deno:
+ // Deno.args is already as specified.
+
+ const { args } = Deno;
+ globalThis[NAMESPACE] = {
+ args
+ };
+} else {
+ // Unknown runtime:
+ // Warn and create mock API.
+
+ console.warn('[cli-api-polyfill] Unknown runtime!');
+
+ globalThis[NAMESPACE] = {
+ args: []
+ };
+}