update: if and for nodes

src/renderer.zig

@@ -65,16 +65,21 @@ pub const Renderer = struct {
         }
 
         for (nodes) |node| {
-            try self.renderNode(alloc, node, writer);
+            try self.renderNode(alloc, node, writer, null);
         }
     }
 
-    fn renderNode(self: *const Renderer, alloc: Allocator, node: parser.Node, writer: anytype) RenderError!void {
+    fn renderNode(self: *const Renderer, alloc: Allocator, node: parser.Node, writer: anytype, context: ?*Context) RenderError!void {
         switch (node.type) {
             .text => try writer.writeAll(node.text.?.content),
             .variable => {
                 const var_name = node.variable.?.expr;
-                var value: Value = self.context.get(var_name) orelse Value.null;
+                var value: Value = Value.null;
+                if (context != null) {
+                    value = context.?.get(var_name) orelse Value.null;
+                }else{
+                    value = self.context.get(var_name) orelse Value.null;
+                }
 
                 var is_safe = false;
 
@@ -99,7 +104,42 @@ pub const Renderer = struct {
                 try self.valueToString(alloc, &buf, value);
                 try writer.writeAll(buf.items);
             },
-            else => unreachable,
+
+            .if_block => {
+                const condition = self.evaluateCondition(node.@"if".?.condition) catch return false;
+
+                if (condition) {
+                    for (node.@"if".?.true_body) |child| {
+                        try self.renderNode(alloc, child, writer, null);
+                    }
+                } else {
+                    for (node.@"if".?.false_body) |child| {
+                        try self.renderNode(alloc, child, writer, null);
+                    }
+                }
+            },
+            .for_block => {
+                const list_value = self.context.get(node.@"for".?.iterable) orelse Value.null;
+                const list = switch (list_value) {
+                    .list => |l| l,
+                    else => return,
+                };
+
+                for (list) |item| {
+                    var ctx = Context.init(alloc);
+                    defer ctx.deinit();
+
+                    try ctx.set(node.@"for".?.loop_var,item);
+
+                    for (node.@"for".?.body) |child| {
+                        try self.renderNode(alloc, child, writer, &ctx);
+                    }
+                    for (node.@"for".?.empty_body) |child| {
+                        try self.renderNode(alloc, child, writer, &ctx);
+                    }
+                }
+            },
+            else => {},
         }
     }
 
@@ -116,4 +156,17 @@ pub const Renderer = struct {
             .dict => try w.writeAll("{dict}"),
         }
     }
+
+    fn evaluateCondition(self: *const Renderer, expr: []const u8) !bool {
+        const value = self.context.get(expr) orelse Value.null;
+        return switch (value) {
+            .bool => |b| b,
+            .int => |i| i != 0,
+            .float => |f| f != 0.0,
+            .string => |s| s.len > 0,
+            .list => |l| l.len > 0,
+            .dict => |d| d.count() > 0,
+            .null => false,
+        };
+    }
 };