Slightly better naming
[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     def c_escape(ch):
16         return {
17             '\n': r'\n',
18             '"': r'\"',
19             '\\': r'\\',
20         }.get(ch, ch)
21
22     return 'stringLiteral(runtime, "{}")'.format(
23         ''.join(c_escape(ch for ch in c_string_literal.value)),
24     )
25
26
27 CONSTANT_EXPRESSION_MAPPING = {
28     'true':     'TRUE',
29     'false':    'FALSE',
30 }
31
32 def generate_constant_expression(c_constant_expression):
33     return CONSTANT_EXPRESSION_MAPPING[c_constant_expression.value]
34
35 def generate_symbol_expression(c_symbol_expression):
36     return 'Environment_get(environment, SYMBOL_LIST[{}] /* symbol: {} */)'.format(
37         c_symbol_expression.symbol_list_index,
38         c_symbol_expression.symbol,
39     )
40
41 def generate_expression(c_argument):
42     if isinstance(c_argument, transformation.CNegationExpression):
43         return generate_negation_expression(c_argument)
44
45     if isinstance(c_argument, transformation.CFunctionCallExpression):
46         return generate_function_call(c_argument)
47
48     LITERAL_TYPE_MAPPING = {
49         transformation.CIntegerLiteral: generate_integer_literal,
50         transformation.CStringLiteral: generate_string_literal,
51         transformation.CConstantExpression: generate_constant_expression,
52         transformation.CSymbolExpression: generate_symbol_expression,
53     }
54
55     if type(c_argument) in LITERAL_TYPE_MAPPING:
56         return LITERAL_TYPE_MAPPING[type(c_argument)](c_argument)
57
58     if isinstance(c_argument, transformation.CFunctionCallForFurInfixOperator):
59         return 'builtin${}({}, {})'.format(
60             c_argument.name,
61             generate_expression(c_argument.left),
62             generate_expression(c_argument.right),
63         )
64
65     raise Exception('Could not handle expresssion "{}"'.format(c_argument))
66
67 def generate_negation_expression(c_negation_expression):
68     return 'builtin$negate({})'.format(
69         generate_expression(c_negation_expression.value)
70     )
71
72 def generate_function_call(c_function_call):
73     return '{}({})'.format(
74         c_function_call.name,
75         ', '.join(generate_expression(argument) for argument in c_function_call.arguments),
76     )
77
78 def generate_expression_statement(c_function_call_statement):
79     # TODO Do we need to garbage collect the results of arbitrary statements?
80     return '{};'.format(generate_expression(c_function_call_statement))
81
82 def generate_assignment_statement(c_assignment_statement):
83     return 'Environment_set(environment, SYMBOL_LIST[{}] /* symbol: {} */, {});'.format(
84         c_assignment_statement.target_symbol_list_index,
85         c_assignment_statement.target,
86         generate_expression(c_assignment_statement.expression),
87     )
88
89 def generate_statement(statement):
90     if isinstance(statement, transformation.CAssignmentStatement):
91         return generate_assignment_statement(statement)
92
93     return generate_expression_statement(statement)
94
95 def generate(c_program):
96     template = ENV.get_template('program.c')
97     return template.render(
98         builtins=list(sorted(c_program.builtin_set)),
99         statements=[generate_statement(statement) for statement in c_program.statements],
100         standard_libraries=list(sorted(c_program.standard_libraries)),
101         symbol_list=c_program.symbol_list,
102     )
103
104 if __name__ == '__main__':
105     import unittest
106
107     unittest.main()