Added lambda expressions
[fur] / normalization.py
index 1cddaed..9725b5b 100644 (file)
@@ -1,5 +1,125 @@
 import collections
 
+import desugaring
+import util
+
+NormalVariableExpression = collections.namedtuple(
+    'NormalVariableExpression',
+    [
+        'variable',
+    ],
+)
+
+NormalIntegerLiteralExpression = collections.namedtuple(
+    'NormalIntegerLiteralExpression',
+    [
+        'integer',
+    ],
+)
+
+NormalLambdaExpression = collections.namedtuple(
+    'NormalLambdaExpression',
+    (
+        'argument_name_list',
+        'statement_list',
+    ),
+)
+
+NormalStringLiteralExpression = collections.namedtuple(
+    'NormalStringLiteralExpression',
+    [
+        'string',
+    ],
+)
+
+NormalSymbolExpression = collections.namedtuple(
+    'NormalSymbolExpression',
+    [
+        'symbol',
+    ],
+)
+
+NormalPushStatement = collections.namedtuple(
+    'NormalPushStatement',
+    (
+        'expression',
+    ),
+)
+
+NormalFunctionCallExpression = collections.namedtuple(
+    'NormalFunctionCallExpression',
+    [
+        'metadata',
+        'function_expression',
+        'argument_count',
+    ],
+)
+
+NormalArrayVariableInitializationStatement = collections.namedtuple(
+    'NormalArrayVariableInitializationStatement',
+    [
+        'variable',
+        'items',
+    ],
+)
+
+NormalSymbolArrayVariableInitializationStatement = collections.namedtuple(
+    'NormalSymbolArrayVariableInitializationStatement',
+    [
+        'variable',
+        'symbol_list',
+    ],
+)
+
+NormalVariableInitializationStatement = collections.namedtuple(
+    'NormalVariableInitializationStatement',
+    [
+        'variable',
+        'expression',
+    ],
+)
+
+NormalVariableReassignmentStatement = collections.namedtuple(
+    'NormalVariableReassignmentStatement',
+    [
+        'variable',
+        'expression',
+    ],
+)
+
+NormalExpressionStatement = collections.namedtuple(
+    'NormalExpressionStatement',
+    [
+        'expression',
+    ],
+)
+
+NormalAssignmentStatement = collections.namedtuple(
+    'NormalAssignmentStatement',
+    [
+        'target',
+        'expression',
+    ],
+)
+
+NormalIfElseStatement = collections.namedtuple(
+    'NormalIfElseStatement',
+    [
+        'condition_expression',
+        'if_statement_list',
+        'else_statement_list',
+    ],
+)
+
+NormalFunctionDefinitionStatement = collections.namedtuple(
+    'NormalFunctionDefinitionStatement',
+    [
+        'name',
+        'argument_name_list',
+        'statement_list',
+    ],
+)
+
 NormalProgram = collections.namedtuple(
     'NormalProgram',
     [
@@ -7,13 +127,379 @@ NormalProgram = collections.namedtuple(
     ],
 )
 
-def flatten(iterable):
-    return tuple(item for internal in iterable for item in internal)
+def normalize_integer_literal_expression(counter, expression):
+    variable = '${}'.format(counter)
+    return (
+        counter + 1,
+        (
+            NormalVariableInitializationStatement(
+                variable=variable,
+                expression=NormalIntegerLiteralExpression(integer=expression.integer),
+            ),
+        ),
+        NormalVariableExpression(variable=variable),
+    )
+
+def normalize_lambda_expression(counter, expression):
+    variable = '${}'.format(counter)
+
+    _, statement_list = normalize_statement_list(
+        0,
+        expression.statement_list,
+        assign_result_to='result',
+    )
+
+    return (
+        counter + 1,
+        (
+            NormalVariableInitializationStatement(
+                variable=variable,
+                expression=NormalLambdaExpression(
+                    argument_name_list=expression.argument_name_list,
+                    statement_list=statement_list,
+                ),
+            ),
+        ),
+        NormalVariableExpression(variable=variable),
+    )
+
+NormalListConstructExpression = collections.namedtuple(
+    'NormalListConstructExpression',
+    [
+        'allocate',
+    ],
+)
+
+NormalListAppendStatement = collections.namedtuple(
+    'NormalListAppendStatement',
+    [
+        'list_expression',
+        'item_expression',
+    ],
+)
+
+def normalize_list_literal_expression(counter, expression):
+    list_variable = '${}'.format(counter)
+    counter += 1
+
+    prestatements = [
+        NormalVariableInitializationStatement(
+            variable=list_variable,
+            expression=NormalListConstructExpression(allocate=len(expression.item_expression_list)),
+        ),
+    ]
+
+    list_expression = NormalVariableExpression(variable=list_variable)
+
+    for item_expression in expression.item_expression_list:
+        counter, item_expression_prestatements, normalized = normalize_expression(
+            counter,
+            item_expression,
+        )
+
+        for p in item_expression_prestatements:
+            prestatements.append(p)
+
+        prestatements.append(
+            NormalListAppendStatement(
+                list_expression=list_expression,
+                item_expression=normalized,
+            )
+        )
+
+    return (
+        counter,
+        tuple(prestatements),
+        list_expression,
+    )
+
+def normalize_string_literal_expression(counter, expression):
+    variable = '${}'.format(counter)
+    return (
+        counter + 1,
+        (
+            NormalVariableInitializationStatement(
+                variable=variable,
+                expression=NormalStringLiteralExpression(string=expression.string),
+            ),
+        ),
+        NormalVariableExpression(variable=variable),
+    )
+
+NormalStructureLiteralExpression = collections.namedtuple(
+    'NormalStructureLiteralExpression',
+    [
+        'field_count',
+        'symbol_list_variable',
+        'value_list_variable',
+    ],
+)
+
+def normalize_structure_literal_expression(counter, expression):
+    prestatements = []
+    field_symbol_array = []
+    field_value_array = []
+
+    for symbol_expression_pair in expression.fields:
+        counter, field_prestatements, field_expression = normalize_expression(
+            counter,
+            symbol_expression_pair.expression,
+        )
+
+        for p in field_prestatements:
+            prestatements.append(p)
+
+        field_symbol_array.append(symbol_expression_pair.symbol)
+        field_value_array.append(field_expression)
+
+    symbol_array_variable = '${}'.format(counter)
+    counter += 1
 
-def normalize_statement(statement):
-    return (statement,)
+    prestatements.append(
+        NormalSymbolArrayVariableInitializationStatement(
+            variable=symbol_array_variable,
+            symbol_list=tuple(field_symbol_array),
+        )
+    )
+
+    value_array_variable = '${}'.format(counter)
+    counter += 1
+
+    prestatements.append(
+        NormalArrayVariableInitializationStatement(
+            variable=value_array_variable,
+            items=tuple(field_value_array),
+        )
+    )
+
+    variable = '${}'.format(counter)
+
+    prestatements.append(
+        NormalVariableInitializationStatement(
+            variable=variable,
+            expression=NormalStructureLiteralExpression(
+                field_count=len(expression.fields),
+                symbol_list_variable=symbol_array_variable,
+                value_list_variable=value_array_variable,
+            ),
+        )
+    )
+
+    return (
+        counter + 1,
+        tuple(prestatements),
+        NormalVariableExpression(variable=variable),
+    )
+
+
+def normalize_symbol_expression(counter, expression):
+    variable = '${}'.format(counter)
+    return (
+        counter + 1,
+        (
+            NormalVariableInitializationStatement(
+                variable=variable,
+                expression=NormalSymbolExpression(symbol=expression.symbol),
+            ),
+        ),
+        NormalVariableExpression(variable=variable),
+    )
+
+def normalize_function_call_expression(counter, expression):
+    prestatements = []
+
+    for argument in expression.argument_list:
+        counter, argument_prestatements, normalized_argument = normalize_expression(counter, argument)
+
+        for s in argument_prestatements:
+            prestatements.append(s)
+
+        variable = '${}'.format(counter)
+        prestatements.append(
+            NormalVariableInitializationStatement(
+                variable=variable,
+                expression=normalized_argument,
+            )
+        )
+        prestatements.append(
+            NormalPushStatement(
+                expression=NormalVariableExpression(
+                    variable=variable,
+                ),
+            ),
+        )
+        counter += 1
+
+    counter, function_prestatements, function_expression = normalize_expression(
+        counter,
+        expression.function,
+    )
+
+    for ps in function_prestatements:
+        prestatements.append(ps)
+
+    if not isinstance(function_expression, NormalVariableExpression):
+        function_variable = '${}'.format(counter)
+
+        prestatements.append(
+            NormalVariableInitializationStatement(
+                variable=function_variable,
+                expression=function_expression,
+            )
+        )
+
+        function_expression = NormalVariableExpression(variable=function_variable)
+        counter += 1
+
+    result_variable = '${}'.format(counter)
+
+    prestatements.append(
+        NormalVariableInitializationStatement(
+            variable=result_variable,
+            expression=NormalFunctionCallExpression(
+                metadata=expression.metadata,
+                function_expression=function_expression,
+                argument_count=len(expression.argument_list),
+            ),
+        )
+    )
+
+    return (
+        counter + 1,
+        tuple(prestatements),
+        NormalVariableExpression(variable=result_variable),
+    )
+
+def normalize_if_expression(counter, expression):
+    counter, condition_prestatements, condition_expression = normalize_expression(
+        counter,
+        expression.condition_expression,
+    )
+
+    result_variable = '${}'.format(counter)
+    counter += 1
+
+    counter, if_statement_list = normalize_statement_list(
+        counter,
+        expression.if_statement_list,
+        assign_result_to=result_variable,
+    )
+    counter, else_statement_list = normalize_statement_list(
+        counter,
+        expression.else_statement_list,
+        assign_result_to=result_variable,
+    )
+
+    return (
+        counter,
+        condition_prestatements + (
+            NormalVariableInitializationStatement(
+                variable=result_variable,
+                expression=NormalVariableExpression(variable='builtin$nil'),
+            ),
+            NormalIfElseStatement(
+                condition_expression=condition_expression,
+                if_statement_list=if_statement_list,
+                else_statement_list=else_statement_list,
+            ),
+        ),
+        NormalVariableExpression(variable=result_variable),
+    )
+
+def normalize_expression(counter, expression):
+    return {
+        desugaring.DesugaredFunctionCallExpression: normalize_function_call_expression,
+        desugaring.DesugaredIfExpression: normalize_if_expression,
+        desugaring.DesugaredIntegerLiteralExpression: normalize_integer_literal_expression,
+        desugaring.DesugaredLambdaExpression: normalize_lambda_expression,
+        desugaring.DesugaredListLiteralExpression: normalize_list_literal_expression,
+        desugaring.DesugaredStringLiteralExpression: normalize_string_literal_expression,
+        desugaring.DesugaredStructureLiteralExpression: normalize_structure_literal_expression,
+        desugaring.DesugaredSymbolExpression: normalize_symbol_expression,
+    }[type(expression)](counter, expression)
+
+def normalize_expression_statement(counter, statement):
+    # TODO Normalized will be a NormalVariableExpression, which will go unused
+    # for expression statements in every case except when it's a return
+    # statement. This cases warnings on C compilation. We should only generate
+    # this variable when it will be used on return.
+    counter, prestatements, normalized = normalize_expression(counter, statement.expression)
+
+    return (
+        counter,
+        prestatements,
+        NormalExpressionStatement(expression=normalized),
+    )
+
+def normalize_function_definition_statement(counter, statement):
+    _, statement_list = normalize_statement_list(
+        0,
+        statement.statement_list,
+        assign_result_to='result',
+    )
+    return (
+        counter,
+        (),
+        NormalFunctionDefinitionStatement(
+            name=statement.name,
+            argument_name_list=statement.argument_name_list,
+            statement_list=statement_list,
+        ),
+    )
+
+def normalize_assignment_statement(counter, statement):
+    counter, prestatements, normalized_expression = normalize_expression(counter, statement.expression)
+    return (
+        counter,
+        prestatements,
+        NormalAssignmentStatement(
+            target=statement.target,
+            expression=normalized_expression,
+        ),
+    )
+
+def normalize_statement(counter, statement):
+    return {
+        desugaring.DesugaredAssignmentStatement: normalize_assignment_statement,
+        desugaring.DesugaredExpressionStatement: normalize_expression_statement,
+        desugaring.DesugaredFunctionDefinitionStatement: normalize_function_definition_statement,
+    }[type(statement)](counter, statement)
+
+@util.force_generator(tuple)
+def normalize_statement_list(counter, statement_list, **kwargs):
+    assign_result_to = kwargs.pop('assign_result_to', None)
+
+    assert len(kwargs) == 0
+
+    result_statement_list = []
+
+    for statement in statement_list:
+        counter, prestatements, normalized = normalize_statement(counter, statement)
+        for s in prestatements:
+            result_statement_list.append(s)
+        result_statement_list.append(normalized)
+
+    # TODO The way we fix the last statement is really confusing
+    last_statement = result_statement_list[-1]
+
+    if isinstance(last_statement, NormalExpressionStatement) and isinstance(last_statement.expression, NormalVariableExpression):
+        if assign_result_to is not None:
+            result_expression = result_statement_list.pop().expression
+            result_statement_list.append(
+                NormalVariableReassignmentStatement(
+                    variable=assign_result_to,
+                    expression=result_expression,
+                )
+            )
+
+    return (
+        counter,
+        result_statement_list,
+    )
 
 def normalize(program):
+    _, statement_list = normalize_statement_list(0, program.statement_list)
+
     return NormalProgram(
-        statement_list=flatten(normalize_statement(s) for s in program.statement_list),
+        statement_list=statement_list,
     )