Chaos: split tables, interactions, Terminal

- Tables are split into `actions` and `goto` now to make formatting
  nicer
- Token is renamed Terminal
- Likes are now Florps
- Lexer now loaded dynamically (badly)
This commit is contained in:
John Doty 2024-05-30 08:02:47 -07:00
parent 71078f76b4
commit 56d24c5fb9
3 changed files with 342 additions and 286 deletions

View file

@ -7,11 +7,12 @@ import select
import sys
import termios
import time
import traceback
import tty
import types
import typing
from dataclasses import dataclass
import grammar
import parser
# from parser import Token, Grammar, rule, seq
@ -47,7 +48,8 @@ def parse(table: parser.ParseTable, tokens, trace=None) -> typing.Tuple[Tree | N
This is not a *great* parser, it's really just a demo for what you can
do with the table.
"""
input: list[str] = [t.value for (t, _, _) in tokens.tokens]
input_tokens = tokens.tokens()
input: list[str] = [t.value for (t, _, _) in input_tokens]
assert "$" not in input
input = input + ["$"]
@ -61,7 +63,7 @@ def parse(table: parser.ParseTable, tokens, trace=None) -> typing.Tuple[Tree | N
current_state = stack[-1][0]
current_token = input[input_index]
action = table.states[current_state].get(current_token, parser.Error())
action = table.actions[current_state].get(current_token, parser.Error())
if trace:
trace(stack, input, input_index, action)
@ -84,21 +86,21 @@ def parse(table: parser.ParseTable, tokens, trace=None) -> typing.Tuple[Tree | N
value = Tree(name=name if not transparent else None, children=tuple(children))
stack = stack[:-size]
goto = table.states[stack[-1][0]].get(name, parser.Error())
assert isinstance(goto, parser.Goto)
stack.append((goto.state, value))
goto = table.gotos[stack[-1][0]].get(name)
assert goto is not None
stack.append((goto, value))
case parser.Shift(state):
stack.append((state, current_token))
input_index += 1
case parser.Error():
if input_index >= len(tokens.tokens):
if input_index >= len(input_tokens):
message = "Unexpected end of file"
start = tokens.tokens[-1][1]
start = input_tokens[-1][1]
else:
message = f"Syntax error: unexpected symbol {current_token}"
(_, start, _) = tokens.tokens[input_index]
(_, start, _) = input_tokens[input_index]
line_index = bisect.bisect_left(tokens.lines, start)
if line_index == 0:
@ -147,7 +149,7 @@ def CSI(x: bytes) -> bytes:
return ESC(b"[" + x)
CLEAR = CSI(b"2J")
CLEAR = CSI(b"H") + CSI(b"J")
def enter_alt_screen():
@ -158,15 +160,108 @@ def leave_alt_screen():
sys.stdout.buffer.write(CSI(b"?1049l"))
class DynamicModule:
file_name: str
member_name: str | None
last_time: float | None
module: types.ModuleType | None
def __init__(self, file_name, member_name):
self.file_name = file_name
self.member_name = member_name
self.last_time = None
self.module = None
self.value = None
def _predicate(self, member) -> bool:
if not inspect.isclass(member):
return False
assert self.module is not None
if member.__module__ != self.module.__name__:
return False
return True
def _transform(self, value):
return value
def get(self):
st = os.stat(self.file_name)
if self.last_time == st.st_mtime:
assert self.value is not None
return self.value
self.value = None
if self.module is None:
mod_name = inspect.getmodulename(self.file_name)
if mod_name is None:
raise Exception(f"{self.file_name} does not seem to be a module")
self.module = importlib.import_module(mod_name)
else:
importlib.reload(self.module)
if self.member_name is None:
classes = inspect.getmembers(self.module, self._predicate)
if len(classes) == 0:
raise Exception(f"No grammars found in {self.file_name}")
if len(classes) > 1:
raise Exception(
f"{len(classes)} grammars found in {self.file_name}: {', '.join(c[0] for c in classes)}"
)
cls = classes[0][1]
else:
cls = getattr(self.module, self.member_name)
if cls is None:
raise Exception(f"Cannot find {self.member_name} in {self.file_name}")
if not self._predicate(cls):
raise Exception(f"{self.member_name} in {self.file_name} is not suitable")
self.value = self._transform(cls)
self.last_time = st.st_mtime
return self.value
class DynamicGrammarModule(DynamicModule):
def __init__(self, file_name, member_name, start_rule, generator):
super().__init__(file_name, member_name)
self.start_rule = start_rule
self.generator = generator
def _predicate(self, member) -> bool:
if not super()._predicate(member):
return False
if getattr(member, "build_table", None):
return True
return False
def _transform(self, value):
return value().build_table(start=self.start_rule, generator=self.generator)
class DynamicLexerModule(DynamicModule):
def _predicate(self, member) -> bool:
if not super()._predicate(member):
return False
if getattr(member, "tokens", None):
return True
return False
class Harness:
source: str | None
table: parser.ParseTable | None
tree: Tree | None
def __init__(self, lexer_func, start_rule, source_path):
# self.generator = parser.GenerateLR1
self.generator = parser.GenerateLALR
self.lexer_func = lexer_func
def __init__(self, start_rule, source_path):
self.start_rule = start_rule
self.source_path = source_path
@ -176,10 +271,11 @@ class Harness:
self.tree = None
self.errors = None
self.grammar_file_name = "./grammar.py"
self.last_grammar_time = None
self.grammar_module = None
self.grammar_name = None
self.grammar_module = DynamicGrammarModule(
"./grammar.py", None, self.start_rule, generator=parser.GenerateLALR
)
self.lexer_module = DynamicLexerModule("./grammar.py", None)
def run(self):
while True:
@ -191,71 +287,19 @@ class Harness:
self.update()
# def should_reload_grammar(self):
def load_grammar(self) -> parser.ParseTable:
st = os.stat(self.grammar_file_name)
if self.last_grammar_time == st.st_mtime:
assert self.table is not None
return self.table
self.table = None
if self.grammar_module is None:
mod_name = inspect.getmodulename(self.grammar_file_name)
if mod_name is None:
raise Exception(f"{self.grammar_file_name} does not seem to be a module")
self.grammar_module = importlib.import_module(mod_name)
else:
importlib.reload(self.grammar_module)
def is_grammar(cls):
if not inspect.isclass(cls):
return False
assert self.grammar_module is not None
if cls.__module__ != self.grammar_module.__name__:
return False
if getattr(cls, "build_table", None):
return True
return False
if self.grammar_name is None:
classes = inspect.getmembers(self.grammar_module, is_grammar)
if len(classes) == 0:
raise Exception(f"No grammars found in {self.grammar_file_name}")
if len(classes) > 1:
raise Exception(
f"{len(classes)} grammars found in {self.grammar_file_name}: {', '.join(c[0] for c in classes)}"
)
grammar_func = classes[0][1]
else:
cls = getattr(self.grammar_module, self.grammar_name)
if cls is None:
raise Exception(f"Cannot find {self.grammar_name} in {self.grammar_file_name}")
if not is_grammar(cls):
raise Exception(
f"{self.grammar_name} in {self.grammar_file_name} does not seem to be a grammar"
)
grammar_func = cls
self.table = grammar_func().build_table(start=self.start_rule, generator=self.generator)
self.last_grammar_time = st.st_mtime
assert self.table is not None
return self.table
return self.grammar_module.get()
def update(self):
start_time = time.time()
try:
table = self.load_grammar()
lexer_func = self.lexer_module.get()
with open(self.source_path, "r", encoding="utf-8") as f:
self.source = f.read()
self.tokens = self.lexer_func(self.source)
self.tokens = lexer_func(self.source)
lex_time = time.time()
# print(f"{tokens.lines}")
@ -268,7 +312,9 @@ class Harness:
except Exception as e:
self.tree = None
self.errors = [f"Error loading grammar: {e}"]
self.errors = ["Error loading grammar:"] + [
" " + l.rstrip() for fl in traceback.format_exception(e) for l in fl.splitlines()
]
parse_elapsed = time.time() - start_time
table = None
@ -276,7 +322,7 @@ class Harness:
rows, cols = termios.tcgetwinsize(sys.stdout.fileno())
if table is not None:
states = table.states
states = table.actions
average_entries = sum(len(row) for row in states) / len(states)
max_entries = max(len(row) for row in states)
print(
@ -320,7 +366,6 @@ if __name__ == "__main__":
enter_alt_screen()
h = Harness(
lexer_func=grammar.FineTokens,
start_rule="file",
source_path=source_path,
)