FurSymbolExpression = collections.namedtuple(
'FurSymbolExpression',
[
- 'value',
+ 'symbol',
],
)
],
)
+FurIfExpression = collections.namedtuple(
+ 'FurIfExpression',
+ [
+ 'condition_expression',
+ 'if_statement_list',
+ 'else_statement_list',
+ ],
+)
+
def _integer_literal_expression_parser(index, tokens):
failure = (False, index, None)
def _symbol_expression_parser(index, tokens):
if tokens[index].type == 'symbol':
- return (True, index + 1, FurSymbolExpression(value=tokens[index].match))
+ return (True, index + 1, FurSymbolExpression(symbol=tokens[index].match))
return (False, index, None)
return True, index, function
-_expression_parser = _or_level_expression_parser
+def _if_expression_parser(index, tokens):
+ failure = (False, index, None)
+
+ if tokens[index].match == 'if':
+ index += 1
+ else:
+ return failure
+
+ success, index, condition_expression = _or_level_expression_parser(index, tokens)
+
+ if not success:
+ raise Exception('Expected condition after "if" on line {}'.format(tokens[index].line))
+
+ if tokens[index].match == 'do':
+ index += 1
+ else:
+ raise Exception('Expected "do" after "if" on line {}'.format(tokens[index].line))
+
+
+ success, index, if_statement_list = _zero_or_more_parser(tuple, _statement_parser)(index, tokens)
+ _, index, _ = consume_newlines(index, tokens)
+
+ if tokens[index].match == 'else':
+ index += 1
+ success, index, else_statement_list = _zero_or_more_parser(tuple, _statement_parser)(index, tokens)
+ _, index, _ = consume_newlines(index, tokens)
+ else:
+ else_statement_list = ()
+
+ if tokens[index].match == 'end':
+ index += 1
+ else:
+ raise Exception('Expected "end" after "if" on line {}'.format(tokens[index].line))
+
+ return (
+ True,
+ index,
+ FurIfExpression(
+ condition_expression=condition_expression,
+ if_statement_list=if_statement_list,
+ else_statement_list=else_statement_list,
+ ),
+ )
+
+
+
+
+_expression_parser = _or_parser(
+ _or_level_expression_parser,
+ _if_expression_parser, # This should always be at the top level
+)
def _expression_statement_parser(index, tokens):
failure = (False, index, None)
tokens[index].line,
))
- if tokens[index].type == 'symbol' and tokens[index].match == 'do':
+ if tokens[index].match == 'do':
index += 1
else:
return failure
return True, index, FurFunctionDefinitionStatement(
name=name,
- argument_name_list=tuple(an.value for an in argument_name_list),
+ argument_name_list=tuple(an.symbol for an in argument_name_list),
statement_list=statement_list,
)