add wasm qr decode

deno_wasm_qr/parse_qr.ts

@@ -0,0 +1,14 @@
+const wasmCode = await Deno.readFile("./decodeqr/target/wasm32-unknown-unknown/release/decodeqr.wasm");
+const wasmModule = new WebAssembly.Module(wasmCode);
+const wasmInstance = new WebAssembly.Instance(wasmModule);
+
+const linearMemory = wasmInstance.exports.memory;
+
+function readString(memory, ptr) {
+    const mem = new Uint8Array(memory.buffer, ptr);
+    let length;
+    for (length = 0; mem[length] !== 0; length ++);
+    return new TextDecoder("utf-8").decode(new Uint8Array(mem.buffer, ptr, length));
+}
+
+console.log(readString(linearMemory, wasmInstance.exports.parse_default_qr()));