logik2021/code/aussagenlogik/syntaxbaum.py

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#!/usr/bin/env python3
# -*- coding: utf-8 -*-
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# IMPORTS
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
from __future__ import annotations;
from lark import Tree;
from typing import Generator;
from typing import List;
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# GLOBALE KONSTANTEN
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# KLASSE: Syntaxbaum
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
class SyntaxBaum(object):
expr: str;
kind: str;
children: List[SyntaxBaum];
tree: Tree;
def __init__(self, fml: Tree):
self.kind = fml.data;
if len(fml.children) == 1 and isinstance(fml.children[0], str):
self.expr = fml.children[0];
self.children = [];
self.tree = Tree(self.kind, fml.children);
else:
self.children = [ SyntaxBaum(child) for child in fml.children if isinstance(child, Tree) and child.data != 'symb' ];
self.tree = Tree(self.kind, [child.tree for child in self.children]);
signature_parts = [];
i = 0;
for subfml in fml.children:
if isinstance(subfml, str):
signature_parts.append(subfml);
elif subfml.data == 'symb':
symb = str(subfml.children[0]);
signature_parts.append(symb);
else:
signature_parts.append('{{{}}}'.format(i));
i += 1;
signature = ' '.join(signature_parts);
self.expr = signature.format(*self.children);
if self.kind in [ 'konj', 'konj_lang', 'disj', 'disj_lang', 'impl' ]:
lbrace = '(' if self.expr.startswith('(') else '( ';
rbrace = ')' if self.expr.endswith(')') else ' )';
self.expr = lbrace + self.expr + rbrace;
return;
def __str__(self):
return self.expr;
def __iter__(self) -> Generator[SyntaxBaum, None, None]:
for child in self.children:
yield child;
@property
def child(self) -> SyntaxBaum:
return self.children[0];
def pretty(self):
return self.tree.pretty(indent_str='- ');