begin chapter 2.6HEADmain

1 files changed, 49 insertions, 0 deletions

diff --git a/ast/ast.odin b/ast/ast.odin
index 67039a3..8007e54 100644
--- a/ast/ast.odin
+++ b/ast/ast.odin
@@ -1,6 +1,9 @@
 package ast
 
 import "../token"
+import "core:bytes"
+
+THIRTY_TWO_KILOBYTES := 262144
 
 Node :: union {
 	Program,
@@ -28,6 +31,11 @@ Return_Statement :: struct {
     return_value: Expression,
 }
 
+Expression_Statement :: struct {
+    token: token.Token,
+    expression: Expression,
+}
+
 Expression :: union {
 	Identifier,
 }
@@ -51,6 +59,8 @@ token_literal :: proc(node: Node) -> (literal: string) {
 			literal = token.literal(s.token)
         case Return_Statement:
             literal = token.literal(s.token)
+        case Expression_Statement:
+            literal = token.literal(s.token)
 		}
 	case Expression:
 		switch e in n {
@@ -60,3 +70,42 @@ token_literal :: proc(node: Node) -> (literal: string) {
 	}
 	return literal
 }
+
+node_to_string :: proc(node: Node) -> string {
+    out: bytes.Buffer
+    bytes.buffer_init_allocator(&out, 4, THIRTY_TWO_KILOBYTES, context.temp_allocator)
+
+	switch n in node {
+	case Program:
+        for stmt in n {
+            bytes.buffer_write_string(&out, node_to_string(n))
+        }
+	case Statement:
+		switch s in n {
+		case Let_Statement:
+			bytes.buffer_write_string(&out, token.literal(s.token) + " ")
+			bytes.buffer_write_string(&out, node_to_string(s.name))
+			bytes.buffer_write_string(&out, " = ")
+            if s.value != nil {
+                bytes.buffer_write_string(&out, node_to_string(s.value))
+            }
+            bytes.buffer_write_string(&out, ";")
+        case Return_Statement:
+			bytes.buffer_write_string(&out, token.literal(s.token) + " ")
+            if s.return_value != nil {
+                bytes.buffer_write_string(&out, node_to_string(s.return_value))
+            }
+        case Expression_Statement:
+            if s.expression != nil {
+                bytes.buffer_write_string(&out, node_to_string(s.expression))
+            }
+		}
+	case Expression:
+		switch e in n {
+		case Identifier:
+			literal = token.literal(e.token)
+		}
+	}
+
+	return bytes.buffer_to_string(&out)
+}