Added ExactConceptParser

This commit is contained in:
2019-11-09 17:29:50 +01:00
parent a636198222
commit 576ce77740
12 changed files with 603 additions and 169 deletions
+319
View File
@@ -0,0 +1,319 @@
from dataclasses import dataclass
from enum import Enum
class TokenKind(Enum):
EOF = "eof"
WHITESPACE = "whitespace"
NEWLINE = "newline"
KEYWORD = "keyword"
IDENTIFIER = "identifier"
STRING = "string"
NUMBER = "number"
TRUE = "true"
FALSE = "false"
LPAR = "lpar"
RPAR = "rpar"
LBRACKET = "lbrace"
RBRACKET = "rbracket"
LBRACE = "lbrace"
RBRACE = "rbrace"
PLUS = "plus"
MINUS = "minus"
STAR = "star"
SLASH = "slash"
PERCENT = "percent"
COMMA = "comma"
SEMICOLON = "semicolon"
COLON = "colon"
DOT = "dot"
QMARK = "qmark"
VBAR = "vbar"
AMPER = "amper"
EQUALS = "="
AT = "at"
BACK_QUOTE = "bquote" # `
BACK_SLASH = "bslash" # \
CARAT = "carat" # ^
DOLLAR = "dollar" # $
EMARK = "emark" # !
GREATER = "greater" # >
LESS = "less" # <
HASH = "HASH" # #
TILDE = "tilde" # ~
UNDERSCORE = "underscore" # _
DEGREE = "degree" # °
@dataclass()
class Token:
type: TokenKind
value: object
index: int
line: int
column: int
@dataclass()
class LexerError(Exception):
message: str
text: str
index: int
line: int
column: int
class Keywords(Enum):
DEF = "def"
CONCEPT = "concept"
AS = "as"
WHERE = "where"
PRE = "pre"
POST = "post"
class Tokenizer:
"""
Class that can iterate on the tokens
"""
KEYWORDS = set(x.value for x in Keywords)
def __init__(self, text):
self.text = text
self.text_len = len(text)
self.column = 1
self.line = 1
self.i = 0
def __iter__(self):
while self.i < self.text_len:
c = self.text[self.i]
if c == "+":
if self.i + 1 < self.text_len and self.text[self.i + 1].isdigit():
number = self.eat_number(self.i)
yield Token(TokenKind.NUMBER, number, self.i, self.line, self.column)
self.i += len(number)
self.column += len(number)
else:
yield Token(TokenKind.PLUS, "+", self.i, self.line, self.column)
self.i += 1
self.column += 1
elif c == "-":
if self.i + 1 < self.text_len and self.text[self.i + 1].isdigit():
number = self.eat_number(self.i)
yield Token(TokenKind.NUMBER, number, self.i, self.line, self.column)
self.i += len(number)
self.column += len(number)
else:
yield Token(TokenKind.MINUS, "-", self.i, self.line, self.column)
self.i += 1
self.column += 1
elif c == "/":
yield Token(TokenKind.SLASH, "/", self.i, self.line, self.column)
self.i += 1
self.column += 1
elif c == "*":
yield Token(TokenKind.STAR, "*", self.i, self.line, self.column)
self.i += 1
self.column += 1
elif c == "{":
yield Token(TokenKind.LBRACE, "{", self.i, self.line, self.column)
self.i += 1
self.column += 1
elif c == "}":
yield Token(TokenKind.RBRACE, "}", self.i, self.line, self.column)
self.i += 1
self.column += 1
elif c == "(":
yield Token(TokenKind.LPAR, "(", self.i, self.line, self.column)
self.i += 1
self.column += 1
elif c == ")":
yield Token(TokenKind.RPAR, ")", self.i, self.line, self.column)
self.i += 1
self.column += 1
elif c == "[":
yield Token(TokenKind.LBRACKET, "[", self.i, self.line, self.column)
self.i += 1
self.column += 1
elif c == "]":
yield Token(TokenKind.RBRACKET, "]", self.i, self.line, self.column)
self.i += 1
self.column += 1
elif c == "=":
yield Token(TokenKind.EQUALS, "=", self.i, self.line, self.column)
self.i += 1
self.column += 1
elif c == " " or c == "\t":
whitespace = self.eat_whitespace(self.i)
yield Token(TokenKind.WHITESPACE, whitespace, self.i, self.line, self.column)
self.i += len(whitespace)
self.column += len(whitespace)
elif c == ",":
yield Token(TokenKind.COMMA, ",", self.i, self.line, self.column)
self.i += 1
self.column += 1
elif c == ".":
yield Token(TokenKind.DOT, ".", self.i, self.line, self.column)
self.i += 1
self.column += 1
elif c == ";":
yield Token(TokenKind.SEMICOLON, ";", self.i, self.line, self.column)
self.i += 1
self.column += 1
elif c == ":":
yield Token(TokenKind.COLON, ":", self.i, self.line, self.column)
self.i += 1
self.column += 1
elif c == "?":
yield Token(TokenKind.QMARK, "?", self.i, self.line, self.column)
self.i += 1
self.column += 1
elif c == "|":
yield Token(TokenKind.VBAR, "|", self.i, self.line, self.column)
self.i += 1
self.column += 1
elif c == "&":
yield Token(TokenKind.AMPER, "&", self.i, self.line, self.column)
self.i += 1
self.column += 1
elif c == "\n" or c == "\r":
newline = self.eat_newline(self.i)
yield Token(TokenKind.NEWLINE, newline, self.i, self.line, self.column)
self.i += len(newline)
self.column = 1
self.line += 1
elif c.isalpha() or c == "_":
identifier = self.eat_identifier(self.i)
token_type = TokenKind.KEYWORD if identifier in self.KEYWORDS else TokenKind.IDENTIFIER
value = Keywords(identifier) if identifier in self.KEYWORDS else identifier
yield Token(token_type, value, self.i, self.line, self.column)
self.i += len(identifier)
self.column += len(identifier)
elif c.isdigit():
number = self.eat_number(self.i)
yield Token(TokenKind.NUMBER, number, self.i, self.line, self.column)
self.i += len(number)
self.column += len(number)
elif c == "'" or c == '"':
string, newlines = self.eat_string(self.i, self.line, self.column)
yield Token(TokenKind.STRING, string, self.i, self.line, self.column) # quotes are kept
self.i += len(string)
self.column = 1 if newlines > 0 else self.column + len(string)
self.line += newlines
else:
raise LexerError(f"Unknown token '{c}'", self.text, self.i, self.line, self.column)
yield Token(TokenKind.EOF, "", self.i, self.line, self.column)
def eat_whitespace(self, start):
result = self.text[start]
i = start + 1
while i < self.text_len:
c = self.text[i]
if c == " " or c == "\t":
result += c
i += 1
else:
break
return result
def eat_newline(self, start):
if start + 1 == self.text_len:
return self.text[start]
current = self.text[start]
next = self.text[start + 1]
if current == "\n" and next == "\r" or current == "\r" and next == "\n":
return current + next
return current
def eat_identifier(self, start):
result = self.text[start]
i = start + 1
while i < self.text_len:
c = self.text[i]
if c.isalpha() or c == "_" or c == "-" or c.isdigit():
result += c
i += 1
else:
break
return result
def eat_number(self, start):
result = self.text[start]
i = start + 1
while i < self.text_len:
c = self.text[i]
if c.isdigit() or c == ".":
result += c
i += 1
else:
break
return result
def eat_string(self, start_index, start_line, start_column):
quote = self.text[start_index]
result = self.text[start_index]
lines_count = 0
i = start_index + 1
escape = False
newline = None
while i < self.text_len:
c = self.text[i]
result += c
i += 1
if newline:
lines_count += 1
newline = c if c == newline else None
else:
if c == "\r" or c == "\n":
newline = c
if c == "\\":
escape = True
elif c == quote and not escape:
break
else:
escape = False
# add trailing new line if needed
if newline:
lines_count += 1
if result[-1] != quote:
raise LexerError("Missing Trailing quote", result, i, start_line + lines_count,
1 if lines_count > 0 else start_column + len(result))
return result, lines_count
def seek(self, words):
if self.i == self.text_len:
return 0
# init
offsets = {}
start_index = self.i
buffer = ""
while self.i < self.text_len:
c = self.text[self.i]
# skip white space
if c in (" ", "\t"):
self.i += 1
continue
for word in words:
if c == word[offset]:
os