If-Else Parsing

1 files changed, 43 insertions, 0 deletions

diff --git a/ast/ast.go b/ast/ast.go
index b2634d4..31b1be1 100644
--- a/ast/ast.go
+++ b/ast/ast.go
@@ -88,6 +88,24 @@ func (i *Identifier) String() string {
 	return i.Value
 }
 
+// BlockStatement represents a block statement.
+type BlockStatement struct {
+	Token   	tokens.Token // the token.LBRACE token
+	Statements 	[]Statement
+}
+
+func (bs *BlockStatement) statementNode() {}
+func (bs *BlockStatement) TokenLiteral() string { return bs.Token.Literal }
+func (bs *BlockStatement) String() string {
+	var out bytes.Buffer	
+
+	for _, s := range bs.Statements {
+		out.WriteString(s.String())
+	}
+
+	return out.String()
+}
+
 // ReturnStatement represents a return statement.
 type ReturnStatement struct {
 	Token       tokens.Token // the token.RETURN token
@@ -204,3 +222,28 @@ func (b *Boolean) TokenLiteral() string {
 func (b *Boolean) String() string {
 	return b.Token.Literal
 }
+
+type IfExpression struct {
+	Token 		tokens.Token // the 'if' token
+	Condition 	Expression
+	Consequence *BlockStatement
+	Alternative *BlockStatement
+}
+
+func (ie *IfExpression) expressionNode() 	{}
+func (ie *IfExpression) TokenLiteral() string { return ie.Token.Literal }
+func (ie *IfExpression) String() string {
+	var out bytes.Buffer
+
+	out.WriteString("if")
+	out.WriteString(ie.Condition.String())
+	out.WriteString(" ")
+	out.WriteString(ie.Consequence.String())
+
+	if ie.Alternative != nil {
+		out.WriteString("else ")
+		out.WriteString(ie.Alternative.String())
+	}
+
+	return out.String()
+}