Add support for streaming data

examples/streaming.rs

@@ -0,0 +1,60 @@
+//! Streaming API example for TOON format
+//!
+//! This example demonstrates how to use the streaming API to encode and decode
+//! large datasets without loading everything into memory.
+
+use serde_json::json;
+use std::fs::File;
+use std::io::{BufReader, BufWriter};
+use toon_rust::{decode_stream, encode_stream};
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    // Create a large dataset
+    let items: Vec<_> = (0..100)
+        .map(|i| {
+            json!({
+                "id": i,
+                "name": format!("Product {}", i),
+                "price": (i as f64) * 1.5,
+                "in_stock": i % 2 == 0
+            })
+        })
+        .collect();
+    let data = json!({
+        "products": items,
+        "metadata": {
+            "total": 100,
+            "source": "example"
+        }
+    });
+
+    println!("Encoding large dataset to file using streaming...");
+
+    // Encode using streaming API - writes directly to file without building string in memory
+    let file = File::create("example_output.toon")?;
+    let mut writer = BufWriter::new(file);
+    encode_stream(&data, &mut writer, None)?;
+    drop(writer); // Ensure buffer is flushed
+
+    println!("✓ Encoded to example_output.toon");
+
+    println!("\nDecoding from file using streaming...");
+
+    // Decode using streaming API - reads incrementally without loading entire file
+    let file = File::open("example_output.toon")?;
+    let decoded = decode_stream(file, None)?;
+
+    println!("✓ Decoded successfully");
+    println!("\nDecoded data summary:");
+    println!(
+        "  Products: {}",
+        decoded["products"].as_array().unwrap().len()
+    );
+    println!("  Metadata total: {}", decoded["metadata"]["total"]);
+
+    // Clean up
+    std::fs::remove_file("example_output.toon")?;
+    println!("\n✓ Cleaned up example_output.toon");
+
+    Ok(())
+}