Source code for tt.cli.core

"""Core command-line interface for tt."""

import sys

from argparse import (

from tt.errors import (
from tt.expressions import BooleanExpression
from tt.tables import TruthTable
from tt.version import __version__

from .utils import print_err, print_info

def _add_expression_arg(parser):
    """Add the expression argument to a parser."""
        help='Boolean expression to process; surround it in quotes to\n'
             'avoid escaping control characters in your terminal')

def _tokens(opts):
    """Run the ``tokens`` command."""
    b = BooleanExpression(opts.expression)

def _postfix_tokens(opts):
    """Run the ``postfix-tokens`` command."""
    b = BooleanExpression(opts.expression)

def _tree(opts):
    """Run the ``tree`` command."""
    b = BooleanExpression(opts.expression)

def _table(opts):
    """Run the ``table`` command."""
    t = TruthTable(opts.expression)

[docs]def get_parsed_args(args=None): """Get the parsed command line arguments. :param args: The command-line args to parse; if omitted, :data:`sys.argv <python:sys.argv>` will be used. :type args: List[str], optional :return: The :class:`Namespace <python:argparse.Namespace>` object holding the parsed args. :rtype: :class:`argparse.Namespace <python:argparse.Namespace>` """ parser = ArgumentParser( prog='tt', description=( 'tt is a library and command-line utility written in Python for\n' 'interacting with Boolean Algebra expressions. tt is open source\n' 'software and released under the MIT License. Please use\n' '`tt --help` for more information.'), formatter_class=RawTextHelpFormatter) parser.add_argument( '--version', action='version', version='v'+str(__version__), help='program version') sub_parsers = parser.add_subparsers(help='the tt command to run') # tokens sub-parser parser_tokens = sub_parsers.add_parser( 'tokens', help='print the expression\'s tokens in order of appearance') _add_expression_arg(parser_tokens) parser_tokens.set_defaults(func=_tokens) # postfix-tokens sub-parser parser_postfix_tokens = sub_parsers.add_parser( 'postfix-tokens', help='print the expression\'s tokens in postfix order') _add_expression_arg(parser_postfix_tokens) parser_postfix_tokens.set_defaults(func=_postfix_tokens) # tree sub-parser parser_tree = sub_parsers.add_parser( 'tree', help='print the expression\'s tree representation') _add_expression_arg(parser_tree) parser_tree.set_defaults(func=_tree) # table sub-parser parser_table = sub_parsers.add_parser( 'table', help='print the expression\'s truth table') _add_expression_arg(parser_table) parser_table.set_defaults(func=_table) if args is None: args = sys.argv[1:] return parser.parse_args(args)
[docs]def main(args=None): """The main routine to run the tt command-line interface. :param args: The command-line arguments. :type args: List[str], optional :return: The exit code of the program. :rtype: int """ try: if args is None: args = sys.argv[1:] opts = get_parsed_args(args) func = getattr(opts, 'func', None) if func is None: print_err('No command specified; use `tt --help` for options.') return 2 opts.expression = ' '.join(opts.expression) func(opts) return 0 except EmptyExpressionError as e: print_err('Empty expressions are invalid!') return 1 except GrammarError as e: print_err('Error! ', e.message, ':', sep='') print_err(e.expr_str) print_err(' ' * e.error_pos, '^', sep='') return 1 except Exception as e: print_err('Received unexpected error; re-raising it!') raise e