96 lines
2.7 KiB
Python
96 lines
2.7 KiB
Python
"""Tokenizer.py: Definition for Tokenizer class"""
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import logging
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import re
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from typing import List, Optional
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from interpreter._token import Token, make_token, SourceLocation
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class Tokenizer:
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"""This class will take the provided source file and convert it to a list of tokens"""
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TOKEN_MATCH = re.compile(r"""\(|\)|\{|\}|;|(\n)|\+|-|\*|/|<|>|,| """)
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def __init__(self, file_name: str) -> None:
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with open(file_name) as f:
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self.source_text = f.read()
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self.source_index = 0
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self.line_number = 1
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self.source_text = re.sub("(private)|(public)|(protected)", "", self.source_text)
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self.type_name_pattern = re.compile('(char)|(int)|(void)|(double)|(Pixel)') #TODO: make this modular
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self._filename = file_name
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def get_tokens(self) -> List[Token]:
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tokens = []
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while char := self._consume():
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if char.isspace():
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continue
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if self._handle_comments(char):
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continue
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token = self._get_token(char)
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logging.debug(f"found token \"{token}\" on line {self.line_number}")
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tokens.append(make_token(token, SourceLocation(self._filename, self.line_number), self.type_name_pattern))
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return tokens
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def _get_token(self, char: str) -> str:
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token = char
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if not re.match(Tokenizer.TOKEN_MATCH, token):
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while (token_char := self._peek()):
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if re.match(Tokenizer.TOKEN_MATCH, token_char):
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break
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token += self._consume()
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return token
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def _handle_comments(self, char: str) -> bool:
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if char == '/' and self._peek() == '/':
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self._get_line() #skip the entire line
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return True
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elif char == '/' and self._peek() == '*':
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self._consume()
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self._consume_multiline_comment()
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return True
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return False
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def _get_line(self) -> str:
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return self._consume_until('\n')
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def _peek(self, offset:int = 0) -> str:
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if (self.source_index + offset) >= len(self.source_text):
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return ''
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char = self.source_text[self.source_index]
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return char
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def _consume(self) -> str:
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char = self._peek()
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if char == '\n':
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self.line_number += 1
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self.source_index += 1
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return char
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def _consume_multiline_comment(self):
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while self._peek():
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if self._consume() == '*' and self._peek() == '/':
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self._consume()
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break
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def _consume_until(self, end_tag: str) -> str:
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res = ""
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while self._peek() and (char:= self._consume()) != end_tag:
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res += char
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return res |