python stutter.py stutter_code.stt > c_code.c
'''
+import itertools
import re
import string
and not s_expression is True \
and not s_expression is False
+ESCAPE_CHARACTERS = {
+ '\\' : '\\',
+ 'n' : '\n',
+}
+
+def undelimit_string(s):
+ assert len(s) >= 2
+
+ delimiter = s[0]
+ assert delimiter == '"' # This is temporary, " is currently the only delimiter
+ assert s[-1] == delimiter
+
+ escape_characters = dict(ESCAPE_CHARACTERS)
+ escape_characters[delimiter] = delimiter
+
+ s = s[1:-1]
+
+ index = 0
+ result = ''
+
+ while index < len(s):
+ ch = s[index]
+
+ if ch == '\\':
+ index += 1
+
+ # TODO Handle when it's not a valid escape character
+ ch = escape_characters[s[index]]
+
+ index += 1
+ result += ch
+
+ return result
+
+TAB_WIDTH = 4
+
+def indent(string):
+ assert isinstance(string, str)
+
+ def indent_line(line):
+ line = line.rstrip()
+
+ if line == '':
+ return line
+
+ return ' ' * TAB_WIDTH + line
+
+ return '\n'.join(indent_line(line) for line in string.splitlines())
+
# String to s-expressions
+class Symbol(object):
+ def __init__(self, string):
+ self.string = string
+
+ def __eq__(self, other):
+ return self.string == other.string
+
TOKEN = re.compile(r'\s*({})'.format('|'.join('(?P<{}>{})'.format(*token) for token in [
('open_parenthese', r'\('),
('close_parenthese', r'\)'),
+ ('identifier', r'[a-z\-]+'), # We can expand this as needed
('integer_literal', r'\d+'),
+ ('string_literal', r'"(\\"|[^"])*"'),
('unexpected_character', r'.'),
])))
stack[-1].append(tuple(items))
items = stack.pop()
+ elif token.group('identifier'):
+ items.append(Symbol(token.group('identifier')))
+
elif token.group('integer_literal'):
items.append(int(token.group('integer_literal')))
+ elif token.group('string_literal'):
+ items.append(undelimit_string(token.group('string_literal')))
+
elif token.group('unexpected_character'):
raise Exception('Unexpected character {}'.format(
token.group('unexpected_character'),
else:
raise Exception()
-
if len(stack) > 0:
raise Exception('Parenthese opened but not closed')
self.pointer_to = pointer_to
class CArgumentDeclaration(object):
- def __init__(self, type, name):
- assert isinstance(type, CType)
- self.type = type
+ def __init__(self, _type, name):
+ assert isinstance(_type, CType)
+ self._type = _type
self.name = name
class CExpression(object):
class CIntegerLiteralExpression(CExpression):
def __init__(self, integer):
- assert isinstance(integer, int)
+ assert is_integer(integer)
+ self.integer = integer
- # Booleans in Python are integers but we don't want them
- assert not integer is True
- assert not integer is False
+ def __eq__(self, other):
+ assert isinstance(other, CIntegerLiteralExpression)
+ return self.integer == other.integer
- self.integer = integer
+class CStringLiteralExpression(CExpression):
+ def __init__(self, string):
+ assert isinstance(string, str)
+ self.string = string
+
+ def __eq__(self, other):
+ assert isinstance(other, CStringLiteralExpression)
+ return self.string == other.string
+
+class CVariableExpression(CExpression):
+ def __init__(self, name):
+ assert isinstance(name, str)
+ self.name = name
+
+ def __eq__(self, other):
+ assert isinstance(other, CVariableExpression)
+ return self.name == other.name
+
+class CReferenceExpression(CExpression):
+ def __init__(self, referee):
+ assert isinstance(referee, CVariableExpression)
+ self.referee = referee
class CFunctionCallExpression(CExpression):
def __init__(self, name, arguments):
self.name = name
self.arguments = arguments
+ def __eq__(self, other):
+ assert isinstance(other, CFunctionCallExpression)
+ return self.name == other.name and self.arguments == other.arguments
+
class CStatement(object):
pass
def __init__(self, expression):
self.expression = expression
+class CDefinitionStatement(CStatement):
+ def __init__(self, _type, name, definition):
+ assert isinstance(_type, CType)
+ assert isinstance(name, str)
+ assert isinstance(definition, CExpression)
+
+ self._type = _type
+ self.name = name
+ self.definition = definition
+
+class CFunctionBody(object):
+ def __init__(self, statements):
+ statements = list(statements)
+ assert all(isinstance(s, CStatement) for s in statements)
+ self.statements = statements
+
class CFunctionDeclaration(object):
def __init__(self, return_type, name, argument_declaration_list, body):
assert isinstance(return_type, CType)
assert isinstance(argument_declaration_list, list)
assert all(isinstance(ad, CArgumentDeclaration) for ad in argument_declaration_list)
- assert isinstance(body, list)
- assert all(isinstance(s, CStatement) for s in body)
+ assert isinstance(body, CFunctionBody)
self.return_type = return_type
self.name = name
# BEGIN S-expression to C AST layer
-def evaluate_to_c(s_expression):
+def quote_to_c(s_expression):
if is_integer(s_expression):
- return CIntegerLiteralExpression(s_expression)
+ return CFunctionCallExpression(
+ 'makeObjectPointerFromInteger',
+ [CIntegerLiteralExpression(s_expression)],
+ )
- raise Exception('Unable to evaluate expression {} to C'.format(s_expression))
+ if isinstance(s_expression, str):
+ return CFunctionCallExpression(
+ 'makeObjectPointerFromString',
+ [CStringLiteralExpression(s_expression)],
+ )
-def evaluate_all_to_c(s_expressions):
- c_expressions = list(map(evaluate_to_c, s_expressions))
- body = list(map(CExpressionStatement, c_expressions[:-1])) + [CReturnStatement(c_expressions[-1])]
+ if isinstance(s_expression, Symbol):
+ return CFunctionCallExpression(
+ 'getSymbol',
+ [CStringLiteralExpression(s_expression.string)],
+ )
+
+ raise Exception('Not implemented for type {}'.format(type(s_expression)))
+
+def evaluate_application_arguments_to_c(
+ arguments,
+ quote_to_c = quote_to_c,
+ ):
- return CFunctionDeclaration(
- CType('int'),
- 'main',
- [
- CArgumentDeclaration(CType('int'), 'argc'),
- CArgumentDeclaration(CPointerType(CPointerType(CType('char'))), 'argv'),
- ],
- body,
+ if len(arguments) == 0:
+ return CVariableExpression('NULL')
+
+ return CFunctionCallExpression(
+ 'c_cons',
+ (
+ quote_to_c(arguments[0]),
+ evaluate_application_arguments_to_c(arguments[1:]),
+ ),
+ )
+
+def evaluate_application_to_c(
+ s_expression,
+ evaluate_application_arguments_to_c = evaluate_application_arguments_to_c,
+ ):
+
+ assert isinstance(s_expression, tuple)
+ if isinstance(s_expression[0], Symbol):
+ return CFunctionCallExpression(
+ s_expression[0].string,
+ (
+ CReferenceExpression(CVariableExpression('env')),
+ evaluate_application_arguments_to_c(s_expression[1:]),
+ ),
)
-# BEGIN C AST to C source layer
+ raise Exception('Not implemented')
-TAB_WIDTH = 2
+def evaluate_to_c(
+ s_expression,
+ evaluate_application_to_c = evaluate_application_to_c,
+ ):
-def indent(string):
- assert isinstance(string, str)
+ if isinstance(s_expression, tuple):
+ return evaluate_application_to_c(s_expression)
- def indent_line(line):
- line = line.rstrip()
+ if is_integer(s_expression):
+ return CIntegerLiteralExpression(s_expression)
- if line == '':
- return line
+ if isinstance(s_expression, str):
+ return CStringLiteralExpression(s_expression)
- return ' ' * TAB_WIDTH + line
+ raise Exception('Unable to evaluate expression {} to C'.format(s_expression))
- return '\n'.join(indent_line(line) for line in string.splitlines())
+def evaluate_all_to_c(s_expressions):
+ c_expressions = list(map(evaluate_to_c, s_expressions))
+
+ return CFunctionBody(itertools.chain(
+ [CDefinitionStatement(
+ CPointerType(CType('Environment')),
+ 'env',
+ CVariableExpression('NULL'),
+ )],
+ map(CExpressionStatement, c_expressions[:-1]),
+ [CReturnStatement(c_expressions[-1])],
+ ))
+
+# BEGIN C AST to C source layer
def generate_pointer_type(pointer_type):
assert isinstance(pointer_type, CPointerType)
def generate_argument_declaration(argument_declaration):
assert isinstance(argument_declaration, CArgumentDeclaration)
- return '{} {}'.format(generate_type(argument_declaration.type), argument_declaration.name)
+ return '{} {}'.format(
+ generate_type(argument_declaration._type),
+ argument_declaration.name,
+ )
def generate_argument_declaration_list(argument_declarations):
return ', '.join(generate_argument_declaration(ad) for ad in argument_declarations)
assert isinstance(expression, CIntegerLiteralExpression)
return str(expression.integer)
+C_ESCAPE_SEQUENCES = {
+ # Taken from https://en.wikipedia.org/wiki/Escape_sequences_in_C
+ '\x07' : r'\a',
+ '\x08' : r'\b',
+ '\x0c' : r'\f',
+ '\x0a' : r'\n',
+ '\x0d' : r'\r',
+ '\x09' : r'\t',
+ '\x0b' : r'\v',
+ '\x5c' : r'\\',
+ '\x27' : r"\'",
+ '\x22' : r'\"',
+ '\x3f' : r'\?',
+}
+
+def generate_string_literal_expression(expression):
+ assert isinstance(expression, CStringLiteralExpression)
+
+ result = '"'
+
+ for ch in expression.string:
+ result += C_ESCAPE_SEQUENCES.get(ch, ch)
+
+ result += '"'
+
+ return result
+
+def generate_variable_expression(expression):
+ assert isinstance(expression, CVariableExpression)
+ return expression.name
+
+def generate_reference_expression(expression):
+ assert isinstance(expression, CReferenceExpression)
+ return '&{}'.format(generate_variable_expression(expression.referee))
+
def generate_function_call_expression(expression):
assert isinstance(expression, CFunctionCallExpression)
return '{}({})'.format(
def generate_expression(
expression,
generate_integer_literal_expression = generate_integer_literal_expression,
+ generate_string_literal_expression = generate_string_literal_expression,
+ generate_variable_expression = generate_variable_expression,
+ generate_reference_expression = generate_reference_expression,
generate_function_call_expression = generate_function_call_expression,
):
if isinstance(expression, CIntegerLiteralExpression):
return generate_integer_literal_expression(expression)
+ if isinstance(expression, CStringLiteralExpression):
+ return generate_string_literal_expression(expression)
+
+ if isinstance(expression, CVariableExpression):
+ return generate_variable_expression(expression)
+
+ if isinstance(expression, CReferenceExpression):
+ return generate_reference_expression(expression)
+
if isinstance(expression, CFunctionCallExpression):
return generate_function_call_expression(expression)
def generate_return_statement(statement):
return 'return {};'.format(generate_expression(statement.expression))
+def generate_definition_statement(statement):
+ return '{} {} = {};'.format(
+ generate_type(statement._type),
+ statement.name,
+ generate_expression(statement.definition),
+ )
+
def generate_statement(
statement,
generate_expression_statement = generate_expression_statement,
- generate_return_statement = generate_return_statement):
+ generate_return_statement = generate_return_statement,
+ generate_definition_statement = generate_definition_statement):
if isinstance(statement, CExpressionStatement):
return generate_expression_statement(statement)
if isinstance(statement, CReturnStatement):
return generate_return_statement(statement)
- raise Exception('Handling for statements of type {} not implemented'.format(type(statement.type)))
+ if isinstance(statement, CDefinitionStatement):
+ return generate_definition_statement(statement)
+
+ raise Exception('Handling for statements of type {} not implemented'.format(type(statement)))
-def generate_statement_list(statements):
- assert all(isinstance(s, CStatement) for s in statements)
- return '\n'.join(generate_statement(s) for s in statements)
+def generate_function_body(function_body):
+ assert isinstance(function_body, CFunctionBody)
+ return '\n'.join(generate_statement(s) for s in function_body.statements)
FUNCTION_DEFINITION_TEMPLATE = string.Template(
'''
return_type = generate_type(function_declaration.return_type),
name = function_declaration.name,
argument_declaration_list = generate_argument_declaration_list(function_declaration.argument_declaration_list),
- body = indent(generate_statement_list(function_declaration.body)),
+ body = indent(generate_function_body(function_declaration.body)),
+ )
+
+PROGRAM_TEMPLATE = string.Template(
+'''
+#include <assert.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+struct Object;
+typedef struct Object Object;
+
+enum Type
+{
+ CELL,
+ STRING,
+ SYMBOL
+};
+typedef enum Type Type;
+
+#define MAX_TYPE_STRING_LENGTH 7
+
+void typeToString(Type type, char* target)
+{
+ switch(type)
+ {
+ case CELL:
+ snprintf(target, MAX_TYPE_STRING_LENGTH, "CELL");
+ return;
+
+ case STRING:
+ snprintf(target, MAX_TYPE_STRING_LENGTH, "STRING");
+ return;
+
+ case SYMBOL:
+ snprintf(target, MAX_TYPE_STRING_LENGTH, "%s", "SYMBOL");
+ return;
+
+ default:
+ fprintf(stderr, "ERROR: Unknown type");
+ exit(1);
+ }
+}
+
+struct Cell;
+typedef struct Cell Cell;
+struct Cell
+{
+ Object* left;
+ Object* right;
+};
+
+struct Environment;
+typedef struct Environment Environment;
+struct Environment
+{
+ char* key;
+ Object* value;
+ Environment* next;
+};
+
+Environment makeEnvironment(char* key, Object* value, Environment* next)
+{
+ Environment result;
+ result.key = key;
+ result.value = value;
+ result.next = next;
+ return result;
+}
+
+Environment* makeEnvironmentPointerFromEnvironment(Environment env)
+{
+ Environment* result = malloc(sizeof(Environment));
+ *result = env;
+ return result;
+}
+
+Environment* makeEnvironmentPointer(char* key, Object* value, Environment* next)
+{
+ return makeEnvironmentPointerFromEnvironment(makeEnvironment(key, value, next));
+}
+
+union Instance
+{
+ Cell cell;
+ char* string;
+ char* symbol;
+};
+typedef union Instance Instance;
+
+Instance makeInstanceFromCell(Cell cell)
+{
+ Instance result;
+ result.cell = cell;
+ return result;
+}
+
+Instance makeInstanceFromString(char* string)
+{
+ Instance result;
+ result.string = string;
+ return result;
+}
+
+Instance makeInstanceFromSymbol(char* symbol)
+{
+ Instance result;
+ result.symbol = symbol;
+ return result;
+}
+
+struct Object
+{
+ Type type;
+ Instance instance;
+};
+
+Object makeObject(Type t, Instance i)
+{
+ Object result;
+ result.type = t;
+ result.instance = i;
+ return result;
+}
+
+Object makeObjectFromCell(Cell cell)
+{
+ return makeObject(CELL, makeInstanceFromCell(cell));
+}
+
+Object makeObjectFromString(char* string)
+{
+ return makeObject(STRING, makeInstanceFromString(string));
+}
+
+Object makeObjectFromSymbol(char* symbol)
+{
+ return makeObject(SYMBOL, makeInstanceFromSymbol(symbol));
+}
+
+Object* makeObjectPointerFromObject(Object o)
+{
+ Object* result = malloc(sizeof(Object));
+ *result = o;
+ return result;
+}
+
+Object* makeObjectPointerFromCell(Cell cell)
+{
+ return makeObjectPointerFromObject(makeObjectFromCell(cell));
+}
+
+Object* makeObjectPointerFromString(char* string)
+{
+ return makeObjectPointerFromObject(makeObjectFromString(string));
+}
+
+Object* makeObjectPointerFromSymbol(char* symbol)
+{
+ return makeObjectPointerFromObject(makeObjectFromSymbol(symbol));
+}
+
+Object* getSymbol(char* symbol)
+{
+ // This will not always be how this is implemented
+ return makeObjectPointerFromSymbol(symbol);
+}
+
+Cell makeCell(Object* left, Object* right)
+{
+ Cell result;
+ result.left = left;
+ result.right = right;
+ return result;
+}
+
+Object* c_cons(Object* left, Object* right)
+{
+ Cell cell = makeCell(left, right);
+ return makeObjectPointerFromCell(cell);
+}
+
+void c_print(Object* stutter_string)
+{
+ if(stutter_string->type != STRING)
+ {
+ char typeName[MAX_TYPE_STRING_LENGTH];
+ typeToString(stutter_string->type, typeName);
+ fprintf(stderr, "ERROR: Expected type STRING, got type %s.", typeName);
+ exit(1);
+ }
+
+ char* c_string = stutter_string->instance.string;
+ printf("%s", c_string);
+}
+
+bool c_symbol_equal(char* left, char* right)
+{
+ return strcmp(left, right) == 0;
+}
+
+Object* c_evaluate_symbol(Environment* env, Object* s)
+{
+ if(env == NULL)
+ {
+ fprintf(stderr, "ERROR: symbol %s not found.", s->instance.symbol);
+ exit(1);
+ }
+
+ if(c_symbol_equal(env->key, s->instance.symbol))
+ {
+ return env->value;
+ }
+
+ return c_evaluate_symbol(env->next, s);
+}
+
+Object* c_evaluate(Environment** env, Object* o)
+{
+ switch(o->type)
+ {
+ case STRING:
+ return o;
+
+ case SYMBOL:
+ return c_evaluate_symbol(*env, o);
+
+ default:
+ break;
+ }
+
+ char typeName[MAX_TYPE_STRING_LENGTH];
+ typeToString(o->type, typeName);
+ fprintf(stderr, "ERROR: Could not evaluate type %s.", typeName);
+ exit(1);
+}
+
+int countArgs(Object* args)
+{
+ if(args == NULL) return 0;
+
+ assert(args->type == CELL);
+ return 1 + countArgs(args->instance.cell.right);
+}
+
+Object* getArg(int index, Object* args)
+{
+ if(index == 0) return args->instance.cell.left;
+
+ return getArg(index - 1, args->instance.cell.right);
+}
+
+void print(Environment** parent, Object* args)
+{
+ assert(countArgs(args) == 1);
+ Object* stutter_string = c_evaluate(parent, getArg(0, args));
+ c_print(stutter_string);
+}
+
+void define(Environment** parent, Object* args)
+{
+ assert(countArgs(args) == 2);
+ Object* name = getArg(0, args);
+ Object* value = c_evaluate(parent, getArg(1, args));
+
+ assert(name->type == SYMBOL);
+ *parent = makeEnvironmentPointer(name->instance.symbol, value, *parent);
+}
+
+int main(int argc, char** argv)
+{
+$body
+}
+'''.strip())
+
+def generate_program(body):
+ return PROGRAM_TEMPLATE.substitute(
+ body = body,
)
if __name__ == '__main__':
with open(source_file_name, 'r') as source_file:
source = source_file.read()
- result = generate_function_declaration(evaluate_all_to_c(parse_all(source)))
+ result = generate_program(
+ indent(generate_function_body(evaluate_all_to_c(parse_all(source)))),
+ )
+
print(result)
projects / sandbox / blobdiff