Add a parallel sampling case (#34)

examples/usage/parallel_sample.py

@@ -0,0 +1,40 @@
+import sglang as sgl
+
+
+@sgl.function
+def parallel_sample(s, question, n):
+    s += (
+        "Question: Compute 1 + 2 + 3\n"
+        "Reasoning: I need to use a calculator.\n"
+        "Tool: calculator\n"
+        "Answer: 6\n"
+
+        "Question: Compute 3 + 2 + 2\n"
+        "Reasoning: I will try a calculator.\n"
+        "Tool: calculator\n"
+        "Answer: 7\n"
+    )
+    s += "Question: " + question + "\n"
+    forks = s.fork(n)
+    forks += "Reasoning:" + sgl.gen("reasoning", stop="\n") + "\n"
+    forks += "Tool:" + sgl.gen("tool", choices=["calculator", "browser"]) + "\n"
+    forks += "Answer:" + sgl.gen("answer", stop="\n") + "\n"
+    forks.join()
+
+
+sgl.set_default_backend(sgl.OpenAI("gpt-3.5-turbo-instruct"))
+#sgl.set_default_backend(sgl.RuntimeEndpoint("http://localhost:30000"))
+
+state = parallel_sample.run(
+    question="Compute 5 + 2 + 4.",
+    n=5,
+    temperature=1.0
+)
+
+for i in range(5):
+    obj = {
+        "reasoning": state["reasoning"][i],
+        "tool": state["tool"][i],
+        "answer": state["answer"][i],
+    }
+    print(f"[{i}], {obj}")