From 7d519b73b69de726fb8fbc67f9e07c2c261dd1c0 Mon Sep 17 00:00:00 2001
From: Luna <git@l4.pm>
Date: Sat, 30 May 2020 22:56:45 -0300
Subject: [PATCH] add runner support on command cast

---
 src/lang.zig   |  2 +-
 src/runner.zig | 18 +++++++++++++++++-
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/src/lang.zig b/src/lang.zig
index 1a747b9..07d3d50 100644
--- a/src/lang.zig
+++ b/src/lang.zig
@@ -116,7 +116,7 @@ pub const NewCommand = struct {
         };
     }
 
-    pub fn cast(base: *@This(), comptime T: type) ?*T {
+    pub fn cast(base: *const @This(), comptime T: type) ?*const T {
         if (base.tag != T.base_tag)
             return null;
 
diff --git a/src/runner.zig b/src/runner.zig
index eacc3c7..024fa42 100644
--- a/src/runner.zig
+++ b/src/runner.zig
@@ -374,7 +374,23 @@ pub const Runner = struct {
         try image.runPlugin("http://calf.sourceforge.net/plugins/VintageDelay", pos, params);
     }
 
-    fn newRunCommand(self: *@This(), cmd: lang.NewCommand) !void {}
+    fn newRunCommandSingle(
+        self: *@This(),
+        cmd: lang.NewCommand,
+        comptime tag: lang.NewCommand.Tag,
+    ) !void {
+        comptime const typ = lang.NewCommand.tagToType(tag);
+        const command = cmd.cast(typ).?;
+
+        std.debug.warn("{}\n", .{command});
+    }
+
+    fn newRunCommand(self: *@This(), cmd: lang.NewCommand) !void {
+        switch (cmd.tag) {
+            .load => try self.newRunCommandSingle(cmd, .load),
+            else => @panic("TODO"),
+        }
+    }
 
     fn runCommand(self: *Runner, cmd: *lang.Command) !void {
         var params = ParamList.init(self.allocator);