diff --git a/parse.go b/parse.go
index 04ef562..4d9619a 100644
--- a/parse.go
+++ b/parse.go
@@ -15,20 +15,15 @@ func (e *errParse) Error() string {
 }
 
 type parser struct {
-	ast map[string]section
+	ast ast
 	l   *lexer
 	tok token
 }
 
 func newParser(data []byte) *parser {
 	p := parser{
-		ast: map[string]section{
-			"": section{
-				name:  "",
-				props: map[string]property{},
-			},
-		},
-		l: lex(string(data)),
+		ast: newAST(),
+		l:   lex(string(data)),
 	}
 	return &p
 }
@@ -49,31 +44,17 @@ func (p *parser) parse() error {
 		case tokenError:
 			return &errParse{p.l.line, p.l.col, p.tok.val}
 		case tokenSection:
-			var sec section
-			sec, ok := p.ast[p.tok.val]
-			if !ok {
-				sec = section{
-					name:  p.tok.val,
-					props: map[string]property{},
-				}
-			}
+			sec := newSection(p.tok.val)
 			if err := p.parseSection(&sec); err != nil {
 				return err
 			}
-			p.ast[sec.name] = sec
+			p.ast.addSection(sec)
 		case tokenKey:
-			var prop property
-			prop, ok := p.ast[""].props[p.tok.val]
-			if !ok {
-				prop = property{
-					key: p.tok.val,
-					val: []string{},
-				}
-			}
+			prop := newProperty(p.tok.val)
 			if err := p.parseProperty(&prop); err != nil {
 				return err
 			}
-			p.ast[""].props[prop.key] = prop
+			p.ast[""][0].addProperty(prop)
 		}
 	}
 }
@@ -96,31 +77,17 @@ func (p *parser) parseSection(out *section) error {
 		case tokenError:
 			return &errParse{p.l.line, p.l.col, p.tok.val}
 		case tokenKey:
-			var prop property
-			prop, ok := out.props[p.tok.val]
-			if !ok {
-				prop = property{
-					key: p.tok.val,
-					val: []string{},
-				}
-			}
+			prop := newProperty(p.tok.val)
 			if err := p.parseProperty(&prop); err != nil {
 				return err
 			}
-			out.props[prop.key] = prop
+			out.addProperty(prop)
 		case tokenSection:
-			var sec section
-			sec, ok := p.ast[p.tok.val]
-			if !ok {
-				sec = section{
-					name:  p.tok.val,
-					props: map[string]property{},
-				}
-			}
+			sec := newSection(p.tok.val)
 			if err := p.parseSection(&sec); err != nil {
 				return err
 			}
-			p.ast[sec.name] = sec
+			p.ast.addSection(sec)
 		default:
 			return nil
 		}
diff --git a/parse_test.go b/parse_test.go
index 66feb82..43b8b1b 100644
--- a/parse_test.go
+++ b/parse_test.go
@@ -9,30 +9,34 @@ import (
 func TestParse(t *testing.T) {
 	tests := []struct {
 		input string
-		want  map[string]section
+		want  ast
 	}{
 		{
 			input: "version=1.2.3\n\n[user]\nname=root\nshell=/bin/bash",
-			want: map[string]section{
-				"": section{
-					name: "",
-					props: map[string]property{
-						"version": property{
-							key: "version",
-							val: []string{"1.2.3"},
+			want: ast{
+				"": []section{
+					section{
+						name: "",
+						props: map[string]property{
+							"version": property{
+								key: "version",
+								val: []string{"1.2.3"},
+							},
 						},
 					},
 				},
-				"user": section{
-					name: "user",
-					props: map[string]property{
-						"name": property{
-							key: "name",
-							val: []string{"root"},
-						},
-						"shell": property{
-							key: "shell",
-							val: []string{"/bin/bash"},
+				"user": []section{
+					section{
+						name: "user",
+						props: map[string]property{
+							"name": property{
+								key: "name",
+								val: []string{"root"},
+							},
+							"shell": property{
+								key: "shell",
+								val: []string{"/bin/bash"},
+							},
 						},
 					},
 				},
@@ -50,43 +54,49 @@ organization=Acme Widgets Inc.
 server=192.0.2.62
 port=143
 file="payroll.dat"`,
-			want: map[string]section{
-				"": section{
-					name: "",
-					props: map[string]property{
-						"version": property{
-							key: "version",
-							val: []string{"1.2.3"},
+			want: ast{
+				"": []section{
+					section{
+						name: "",
+						props: map[string]property{
+							"version": property{
+								key: "version",
+								val: []string{"1.2.3"},
+							},
 						},
 					},
 				},
-				"owner": section{
-					name: "owner",
-					props: map[string]property{
-						"name": property{
-							key: "name",
-							val: []string{"John Doe"},
-						},
-						"organization": property{
-							key: "organization",
-							val: []string{"Acme Widgets Inc."},
+				"owner": []section{
+					section{
+						name: "owner",
+						props: map[string]property{
+							"name": property{
+								key: "name",
+								val: []string{"John Doe"},
+							},
+							"organization": property{
+								key: "organization",
+								val: []string{"Acme Widgets Inc."},
+							},
 						},
 					},
 				},
-				"database": section{
-					name: "database",
-					props: map[string]property{
-						"server": property{
-							key: "server",
-							val: []string{"192.0.2.62"},
-						},
-						"port": property{
-							key: "port",
-							val: []string{"143"},
-						},
-						"file": property{
-							key: "file",
-							val: []string{`"payroll.dat"`},
+				"database": []section{
+					section{
+						name: "database",
+						props: map[string]property{
+							"server": property{
+								key: "server",
+								val: []string{"192.0.2.62"},
+							},
+							"port": property{
+								key: "port",
+								val: []string{"143"},
+							},
+							"file": property{
+								key: "file",
+								val: []string{`"payroll.dat"`},
+							},
 						},
 					},
 				},