feat: make a better example

examples/.env3

@@ -1,4 +1 @@
-VAR="
-multiline
-variable
-"
+HOME="/home/koyori"

examples/build.zig

@@ -6,7 +6,7 @@ const pkg_path = "../src/lib.zig";
 const examples = .{
     "basic",
     "substitution",
-    "multiline",
+    "dry-run",
 };
 
 pub fn build(b: *std.build.Builder) void {

examples/dry-run/main.zig

@@ -0,0 +1,32 @@
+const std = @import("std");
+const Loader = @import("dotenv").Loader;
+
+pub fn main() !void {
+    const allocator = std.heap.page_allocator;
+
+    std.debug.print(
+        "Before => HOME={s}\n",
+        .{std.os.getenv("HOME") orelse ""},
+    );
+
+    var loader = Loader(.{ .dry_run = true }).init(allocator);
+    defer loader.deinit();
+
+    try loader.loadFromFile(".env3");
+
+    std.debug.print(
+        "After  => HOME={s}\n",
+        .{std.os.getenv("HOME") orelse ""},
+    );
+
+    std.debug.print("Process envs have not been modified!\n\n", .{});
+    std.debug.print("Now list envs from the file:\n", .{});
+
+    var it = loader.envs().iterator();
+    while (it.next()) |*entry| {
+        std.debug.print(
+            "{s}={s}\n",
+            .{ entry.key_ptr.*, entry.value_ptr.*.? },
+        );
+    }
+}