diff --git a/amend/ast.h b/amend/ast.h
new file mode 100644
index 0000000..7834a2b
--- /dev/null
+++ b/amend/ast.h
@@ -0,0 +1,165 @@
+/*
+ * Copyright (C) 2007 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef AMEND_AST_H_
+#define AMEND_AST_H_
+
+#include "commands.h"
+
+typedef struct AmStringValue AmStringValue;
+
+typedef struct {
+    int argc;
+    AmStringValue *argv;
+} AmFunctionArguments;
+
+/* An internal structure used only by the parser;
+ * will not appear in the output AST.
+xxx try to move this into parser.h
+ */
+typedef struct AmFunctionArgumentBuilder AmFunctionArgumentBuilder;
+struct AmFunctionArgumentBuilder {
+    AmFunctionArgumentBuilder *next;
+    AmStringValue *arg;
+    int argCount;
+};
+
+typedef struct AmWordListBuilder AmWordListBuilder;
+struct AmWordListBuilder {
+    AmWordListBuilder *next;
+    const char *word;
+    int wordCount;
+};
+
+typedef struct {
+    const char *name;
+    Function *fn;
+    AmFunctionArguments *args;
+} AmFunctionCall;
+
+
+/* <string-value> ::=
+ *      <literal-string> |
+ *      <function-call>
+ */
+struct AmStringValue {
+    unsigned int line;
+
+    enum {
+        AM_SVAL_LITERAL,
+        AM_SVAL_FUNCTION,
+    } type;
+    union {
+        const char *literal;
+//xxx inline instead of using pointers
+        AmFunctionCall *function;
+    } u;
+};
+
+
+/* <string-comparison-expression> ::=
+ *      <string-value> <string-comparison-operator> <string-value>
+ */
+typedef struct {
+    unsigned int line;
+
+    enum {
+        AM_SOP_LT,
+        AM_SOP_LE,
+        AM_SOP_GT,
+        AM_SOP_GE,
+        AM_SOP_EQ,
+        AM_SOP_NE,
+    } op;
+    AmStringValue *arg1;
+    AmStringValue *arg2;
+} AmStringComparisonExpression;
+
+
+/* <boolean-expression> ::=
+ *      ! <boolean-value> |
+ *      <boolean-value> <binary-boolean-operator> <boolean-value>
+ */
+typedef struct AmBooleanValue AmBooleanValue;
+typedef struct {
+    unsigned int line;
+
+    enum {
+        AM_BOP_NOT,
+
+        AM_BOP_EQ,
+        AM_BOP_NE,
+
+        AM_BOP_AND,
+
+        AM_BOP_OR,
+    } op;
+    AmBooleanValue *arg1;
+    AmBooleanValue *arg2;
+} AmBooleanExpression;
+
+
+/* <boolean-value> ::=
+ *      <boolean-expression> |
+ *      <string-comparison-expression>
+ */
+struct AmBooleanValue {
+    unsigned int line;
+
+    enum {
+        AM_BVAL_EXPRESSION,
+        AM_BVAL_STRING_COMPARISON,
+    } type;
+    union {
+        AmBooleanExpression expression;
+        AmStringComparisonExpression stringComparison;
+    } u;
+};
+
+
+typedef struct {
+    unsigned int line;
+
+    int argc;
+    const char **argv;
+} AmWordList;
+
+
+typedef struct {
+    bool booleanArgs;
+    union {
+        AmWordList *w;
+        AmBooleanValue *b;
+    } u;
+} AmCommandArguments;
+
+typedef struct {
+    unsigned int line;
+
+    const char *name;
+    Command *cmd;
+    AmCommandArguments *args;
+} AmCommand;
+
+typedef struct {
+    AmCommand **commands;
+    int commandCount;
+    int arraySize;
+} AmCommandList;
+
+void dumpCommandList(const AmCommandList *commandList);
+
+#endif  // AMEND_AST_H_