Store functions as objects
[fur] / generation.py
1 import jinja2
2
3 import transformation
4
5 ENV = jinja2.Environment(
6     autoescape=jinja2.select_autoescape([]),
7     loader=jinja2.FileSystemLoader('templates'),
8     trim_blocks=True,
9 )
10
11 def generate_integer_literal(c_integer_literal):
12     return 'integerLiteral({})'.format(c_integer_literal.value)
13
14 def generate_string_literal(c_string_literal):
15     return 'stringLiteral(STRING_LITERAL_LIST[{}])'.format(c_string_literal.index)
16
17 CONSTANT_EXPRESSION_MAPPING = {
18     'true':     'TRUE',
19     'false':    'FALSE',
20 }
21
22 def generate_constant_expression(c_constant_expression):
23     return CONSTANT_EXPRESSION_MAPPING[c_constant_expression.value]
24
25 def generate_symbol_expression(c_symbol_expression):
26     return 'Environment_get(environment, SYMBOL_LIST[{}] /* symbol: {} */)'.format(
27         c_symbol_expression.symbol_list_index,
28         c_symbol_expression.symbol,
29     )
30
31 def generate_variable_expression(expression):
32     return expression.variable
33
34 def generate_expression(expression):
35     if isinstance(expression, transformation.CNegationExpression):
36         return generate_negation_expression(expression)
37
38     if isinstance(expression, transformation.CFunctionCallExpression):
39         return generate_function_call(expression)
40
41     LITERAL_TYPE_MAPPING = {
42         transformation.CIntegerLiteral: generate_integer_literal,
43         transformation.CStringLiteral: generate_string_literal,
44         transformation.CConstantExpression: generate_constant_expression,
45         transformation.CSymbolExpression: generate_symbol_expression,
46     }
47
48     if type(expression) in LITERAL_TYPE_MAPPING:
49         return LITERAL_TYPE_MAPPING[type(expression)](expression)
50
51     if isinstance(expression, transformation.CFunctionCallForFurInfixOperator):
52         return 'operator${}({}, {})'.format(
53             expression.name,
54             generate_expression(expression.left),
55             generate_expression(expression.right),
56         )
57
58     return {
59         transformation.CVariableExpression: generate_variable_expression,
60     }[type(expression)](expression)
61
62 def generate_negation_expression(c_negation_expression):
63     return 'operator$negate({})'.format(
64         generate_expression(c_negation_expression.value)
65     )
66
67 def generate_function_call(function_call):
68     return '{}({}, {})'.format(
69         function_call.name,
70         function_call.argument_count,
71         # TODO This is just a single item containing a reference to the items list--make that clearer
72         generate_expression(function_call.argument_items),
73     )
74
75 def generate_expression_statement(statement):
76     # TODO Do we need to garbage collect the results of arbitrary statements?
77     return '{};'.format(generate_expression(statement.expression))
78
79 def generate_symbol_assignment_statement(c_assignment_statement):
80     return 'Environment_set(environment, SYMBOL_LIST[{}] /* symbol: {} */, {});'.format(
81         c_assignment_statement.target_symbol_list_index,
82         c_assignment_statement.target,
83         generate_expression(c_assignment_statement.expression),
84     )
85
86 def generate_array_variable_initialization_statement(statement):
87     return 'Object {}[] = {{ {} }};'.format(
88         statement.variable,
89         ', '.join(generate_expression(i) for i in statement.items),
90     )
91
92 def generate_variable_initialization_statement(statement):
93     return 'Object {} = {};'.format(
94         statement.variable,
95         generate_expression(statement.expression),
96     )
97
98 def generate_variable_reassignment_statement(statement):
99     return '{} = {};'.format(
100         statement.variable,
101         generate_expression(statement.expression),
102     )
103
104
105 def indent(s):
106     return '\n'.join(' ' * 2 + l for l in s.split('\n'))
107
108 def generate_if_else_statement(statement):
109     # TODO Check that the argument is boolean
110     return 'if({}.instance.boolean)\n{{\n{}\n}}\nelse\n{{\n{}\n}}'.format(
111         generate_expression(statement.condition_expression),
112         indent('\n'.join(generate_statement(s) for s in statement.if_statements)),
113         indent('\n'.join(generate_statement(s) for s in statement.else_statements)),
114     )
115
116 def generate_statement(statement):
117     return {
118         transformation.CExpressionStatement: generate_expression_statement,
119         transformation.CIfElseStatement: generate_if_else_statement,
120         transformation.CSymbolAssignmentStatement: generate_symbol_assignment_statement,
121         transformation.CArrayVariableInitializationStatement: generate_array_variable_initialization_statement,
122         transformation.CVariableInitializationStatement: generate_variable_initialization_statement,
123         transformation.CVariableReassignmentStatement: generate_variable_reassignment_statement,
124     }[type(statement)](statement)
125
126 def generate(program):
127     template = ENV.get_template('program.c')
128     return template.render(
129         builtins=list(sorted(program.builtin_set)),
130         statements=[generate_statement(statement) for statement in program.statements],
131         standard_libraries=list(sorted(program.standard_libraries)),
132         string_literal_list=program.string_literal_list,
133         symbol_list=program.symbol_list,
134     )
135
136 if __name__ == '__main__':
137     import unittest
138
139     unittest.main()