split main code into a runner struct

src/main.zig

@@ -1,6 +1,6 @@
 const std = @import("std");
 
-const scanners = @import("scanner.zig");
+const runners = @import("runner.zig");
 
 const Allocator = std.mem.Allocator;
 
@@ -9,30 +9,14 @@ pub const Result = error{
     CompileError,
 };
 
+pub const StdOut = *std.io.OutStream(std.fs.File.WriteError);
+
 fn run(allocator: *Allocator, data: []u8) !void {
     var stdout_file = try std.io.getStdOut();
     const stdout = &stdout_file.outStream().stream;
 
-    var scanner = scanners.Scanner.init(allocator, data);
-
-    while (true) {
-        var tok_opt = scanner.nextToken() catch |err| {
-            try stdout.print(
-                "error at '{}': {}\n",
-                scanner.currentLexeme(),
-                err,
-            );
-
-            return Result.CompileError;
-        };
-
-        if (tok_opt) |tok| {
-            if (tok.ttype == .EOF) break;
-            try stdout.print("{x}\n", tok);
-        }
-    }
-
-    return Result.Ok;
+    var runner = runners.Runner.init(allocator, stdout);
+    return runner.execute(data);
 }
 
 fn runFile(allocator: *Allocator, path: []const u8) !void {

src/parser.zig

@@ -0,0 +1 @@
+pub const Parser = struct {};

src/runner.zig

@@ -0,0 +1,38 @@
+const std = @import("std");
+const scanners = @import("scanner.zig");
+const main = @import("main.zig");
+
+const Allocator = std.mem.Allocator;
+const Result = main.Result;
+
+pub const Runner = struct {
+    allocator: *Allocator,
+    stdout: main.StdOut,
+
+    pub fn init(allocator: *Allocator, stdout: var) Runner {
+        return Runner{ .allocator = allocator, .stdout = stdout };
+    }
+
+    pub fn execute(self: *Runner, code: []u8) !void {
+        var scanner = scanners.Scanner.init(self.allocator, code);
+
+        while (true) {
+            var tok_opt = scanner.nextToken() catch |err| {
+                try self.stdout.print(
+                    "error at '{}': {}\n",
+                    scanner.currentLexeme(),
+                    err,
+                );
+
+                return Result.CompileError;
+            };
+
+            if (tok_opt) |tok| {
+                if (tok.ttype == .EOF) break;
+                try self.stdout.print("{x}\n", tok);
+            }
+        }
+
+        return Result.Ok;
+    }
+};