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Diffstat (limited to 'nivis-python/lexer.py')
| -rw-r--r-- | nivis-python/lexer.py | 276 |
1 files changed, 0 insertions, 276 deletions
diff --git a/nivis-python/lexer.py b/nivis-python/lexer.py deleted file mode 100644 index 7ba94e3..0000000 --- a/nivis-python/lexer.py +++ /dev/null @@ -1,276 +0,0 @@ -""" -Token and Lexer Documentation -============================= - -This module provides the `Token` and `Lexer` classes for tokenizing input strings. - -Token Class ------------ - -The `Token` class represents a token with a type, value, and position in the input string. It is a subclass of the built-in `dict` class. - -Attributes: -- `type` (str): The type of the token. -- `value` (str or int): The value of the token. -- `position` (int): The position of the token in the input string. - -Methods: -- `__getattr__(self, name)`: Retrieves the value of an attribute by name. Raises an `AttributeError` if the attribute does not exist. - -Lexer Class ------------ - -The `Lexer` class tokenizes an input string using a set of rules. - -Attributes: -- `input` (str): The input string to tokenize. -- `position` (int): The current position in the input string. -- `tokens` (list): The list of tokens generated by the lexer. - -Methods: -- `get_next_token(self)`: Retrieves the next token from the input string. -- `__iter__(self)`: Returns an iterator over the tokens. -- `__getitem__(self, index)`: Retrieves a token by index. -- `__len__(self)`: Returns the number of tokens. - -Usage Example -------------- - -```python -lexer = Lexer(''' -@newMessage: { - ? message == 1: reply: hi - ! reply: no -} -''') - -token = lexer.get_next_token() -while token['type'] != 'EOF': - print(f'Type: {token["type"]}, Value: {token["value"]}, Position: {token["position"]}') - token = lexer.get_next_token() - -print("\nAll tokens:") -print([t['type'] for t in lexer]) -""" -from .exception import ValueError - -__all__ = ["Token", "Lexer"] - - -class Token(dict): - """ - A class representing a token in the lexer. - - Args: - type: The type of the token. - value: The value of the token. - position: The position of the token. - - Returns: - None - - Example: - ```python - token = Token("identifier", "x", (1, 5)) - ``` - """ - - def __init__(self, type, value, position): - """ - Initializes a Token object. - - Args: - type: The type of the token. - value: The value of the token. - position: The position of the token. - - Returns: - None - """ - super().__init__(type=type, value=value, position=position) - - def __getattr__(self, name): - """ - Retrieves the value of an attribute from the Token object. - - Args: - name: The name of the attribute. - - Returns: - The value of the attribute. - - Raises: - AttributeError: Raised when the attribute does not exist. - """ - try: - return self[name] - except KeyError as e: - raise AttributeError(f"'Token' object has no attribute '{name}'") from e - - -class Lexer: - """ - A class representing a lexer for Psi code. - - Args: - input: The input code to be lexed. - - Returns: - None - - Example: - ```python - lexer = Lexer("x = 10") - for token in lexer: - print(token) - ``` - """ - - def __init__(self, input): - """ - Initializes a Lexer object. - - Args: - input: The input code to be lexed. - - Returns: - None - """ - self.input = input - self.position = 0 - self.tokens = [] - - def get_next_token(self): - """ - Retrieves the next token from the input code. - - Returns: - The next token. - - Raises: - Exception: Raised when an unknown character is encountered. - """ - while self.position < len(self.input): - current_char = self.input[self.position] - - if current_char.isspace(): - self.position += 1 - continue - - if current_char == "#": - self.position += 1 - while ( - self.position < len(self.input) - and self.input[self.position] != "\n" - ): - self.position += 1 - continue - - if ( - current_char == "/" - and self.position + 1 < len(self.input) - and self.input[self.position + 1] == "*" - ): - self.position += 2 - while self.position < len(self.input) - 1 and ( - self.input[self.position] != "*" - or self.input[self.position + 1] != "/" - ): - self.position += 1 - if self.position < len(self.input) - 1: - self.position += 2 - continue - - if current_char.isalpha(): - start_position = self.position - while ( - self.position < len(self.input) - and self.input[self.position].isalnum() - ): - self.position += 1 - token = Token( - "IDENTIFIER", - self.input[start_position : self.position], - start_position, - ) - self.tokens.append(token) - return token - - if current_char.isdigit(): - start_position = self.position - while ( - self.position < len(self.input) - and self.input[self.position].isdigit() - ): - self.position += 1 - token = Token( - "INTEGER", - int(self.input[start_position : self.position]), - start_position, - ) - self.tokens.append(token) - return token - - if current_char in {"<", ">", "=", "!", "&", "|", "@"}: - if self.position + 1 < len(self.input) and self.input[ - self.position + 1 - ] in {"=", "&", "|"}: - token = Token( - "OPERATOR", - current_char + self.input[self.position + 1], - self.position, - ) - self.position += 2 - else: - token = Token("OPERATOR", current_char, self.position) - self.position += 1 - self.tokens.append(token) - return token - - if current_char in {"{", "}", "(", ")", "[", "]", ";", ",", ".", ":"}: - return self._extracted_from_get_next_token_64("SEPARATOR", current_char) - if current_char in {"?", "!", "|"}: - return self._extracted_from_get_next_token_64("CONTROL", current_char) - self.position += 1 - raise ValueError(f"Unknown character: {current_char}") - - token = Token("EOF", None, self.position) - self.tokens.append(token) - return token - - # TODO Rename this here and in `get_next_token` - def _extracted_from_get_next_token_64(self, arg0, current_char): - token = Token(arg0, current_char, self.position) - self.position += 1 - self.tokens.append(token) - return token - - def __iter__(self): - """ - Returns an iterator over the tokens. - - Returns: - An iterator over the tokens. - """ - return iter(self.tokens) - - def __getitem__(self, index): - """ - Retrieves the token at the specified index. - - Args: - index: The index of the token. - - Returns: - The token at the specified index. - """ - return self.tokens[index] - - def __len__(self): - """ - Returns the number of tokens. - - Returns: - The number of tokens. - """ - return len(self.tokens) |