_qasmparser.py 文件源码

def __init__(self, filename):
        """Create the parser."""
        if filename is None:
            filename = ""
        self.lexer = QasmLexer(filename)
        self.tokens = self.lexer.tokens
        self.parse_dir = tempfile.mkdtemp(prefix='qiskit')
        self.precedence = (
        ('left', '+', '-'),
        ('left', '*', '/'),
        ('left', 'negative', 'positive'),
        ('right', '^'))
        # For yacc, also, write_tables = Bool and optimize = Bool
        self.parser = yacc.yacc(module=self, debug=False,
                                outputdir=self.parse_dir)
        self.qasm = None
        self.parse_deb = False
        self.global_symtab = {}                          # global symtab
        self.current_symtab = self.global_symtab         # top of symbol stack
        self.symbols = []                                # symbol stack
        self.external_functions = ['sin', 'cos', 'tan', 'exp', 'ln', 'sqrt','acos','atan','asin']