73 lines
1.9 KiB
Python
73 lines
1.9 KiB
Python
from abc import ABCMeta, abstractmethod
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class Context(object):
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"""
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Context class as part of the Interpreter design pattern.
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External Interpreter Pattern documentation: U{https://en.wikipedia.org/wiki/Interpreter_pattern}
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"""
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def __init__(self, in_data):
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"""
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Initialize a new Context class.
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@param in_data: The starting input of this context.
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"""
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self.in_data = in_data
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self.out_data = None
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class Expression(object, metaclass=ABCMeta):
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"""
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Abstract Expression class as part of the Interpreter design pattern.
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External Interpreter Pattern documentation: U{https://en.wikipedia.org/wiki/Interpreter_pattern}
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"""
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@abstractmethod
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def interpret(self, context):
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"""
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Abstract interpret method.
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@param context: The context to interpret.
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@type context: Context
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"""
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pass
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class NonTerminalExpression(Expression, metaclass=ABCMeta):
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"""
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Base class for the NonTerminalExpression class as part of the Interpreter design pattern.
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External Interpreter Pattern documentation: U{https://en.wikipedia.org/wiki/Interpreter_pattern}
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"""
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def __init__(self, **expressions):
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"""
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Initialize a new NonTerminalExpression instance.
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@param expressions: A dict of Expressions that are used in this NonTerminalExpressions production.
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@type expressions: dict
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"""
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self.expressions = expressions
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class TerminalExpression(Expression, metaclass=ABCMeta):
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"""
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Base class for the TerminalExpression class as part of the Interpreter design pattern.
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External Interpreter Pattern documentation: U{https://en.wikipedia.org/wiki/Interpreter_pattern}
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"""
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def __init__(self, literal):
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"""
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Initialize a new TerminalExpression instance.
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@param literal: A literal value representing this TerminalExpression.
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"""
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self.literal = literal
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