Generate hello world Zig code

internal/zig/zig_test.go

@@ -19,21 +19,49 @@ func Expect[T cmp.Ordered](expected, actual T) error {
 func TestHelloWorld(t *testing.T) {
 	expected := `//! Hello, world!
 
+const std = @import("std");
+
 fn main() void {
-    return;
+    std.debug.print("Hello, world!\n", .{});
 }
 `
 
 	root := &zig.Root{
 		ContainerDocComment: "Hello, world!",
 		ContainerMembers: []*zig.ContainerMember{
+			{
+				Decl: &zig.GlobalVarDecl{
+					Const: true,
+					Name:  "std",
+					Value: &zig.CallExpr{
+						Fun: &zig.Identifier{Name: "@import"},
+						Args: []zig.Expr{
+							&zig.Literal{Kind: "string", Value: "std"},
+						},
+					},
+				},
+			},
 			{
 				Decl: &zig.FnDecl{
 					Name:       "main",
 					ReturnType: &zig.Identifier{Name: "void"},
 					Body: &zig.Block{
 						Stmts: []zig.Stmt{
-							&zig.ReturnStmt{},
+							&zig.ExprStmt{
+								Expr: &zig.CallExpr{
+									Fun: &zig.FieldAccessExpr{
+										Receiver: &zig.FieldAccessExpr{
+											Receiver: &zig.Identifier{Name: "std"},
+											Field:    "debug",
+										},
+										Field: "print",
+									},
+									Args: []zig.Expr{
+										&zig.Literal{Kind: "string", Value: "Hello, world!\n"},
+										&zig.InitListExpr{Empty: true},
+									},
+								},
+							},
 						},
 					},
 				},