72 lines
1.6 KiB
Python
Executable File
72 lines
1.6 KiB
Python
Executable File
class Token:
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# Represents the single smallest unit that makes up an expression.
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def __init__(self, value, type, is_negative_variable = False):
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self.value = value
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self.type = type
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self.is_negative_variable = is_negative_variable
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def __str__(self):
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return "Value: %s" %(self.value)
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class TokenType:
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add = 0
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subtract = 1
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multiply = 2
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divide = 3
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power = 4
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variable = 5
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constant = 6
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exp_start = 7
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exp_end = 8
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unknown = 9
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OPERATOR_VERBS = {
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0 : "Adding",
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1 : "Subtracting",
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2 : "Multiplying",
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3 : "Dividing",
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4 : "Raising"
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}
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TOKEN_NAMES = {
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0 : "Addition",
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1 : "Subtraction",
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2 : "Multiplication",
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3 : "Division",
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4 : "Power",
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5 : "Variable",
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6 : "Constant",
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7 : "Expression Start",
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8 : "Expression End",
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9 : "Unknown"
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}
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OPERATORS = {
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'+' : add,
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'-' : subtract,
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'*' : multiply,
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'^' : power,
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'/' : divide
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}
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@staticmethod
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def get_operator_verb(token):
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# Returns the verb that corresponds to the supplied Token object's value field, or
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# throws an error if the Token object isn't a mathmatical operator.
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if not token in TokenType.OPERATOR_VERBS:
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raise ValueError("An operator verb could not be found.", "token")
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return TokenType.OPERATOR_VERBS[token]
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@staticmethod
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def get_operator(character):
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# Accepts an individual character and returns either the mathmatical operator TokenType or unknown.
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if not character in TokenType.OPERATORS:
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return TokenType.unknown
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return TokenType.OPERATORS[character]
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@staticmethod
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def get_token_type_name(tokenType):
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# Returns the token's full name based on the TokenType value.
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return TokenType.TOKEN_NAMES[tokenType]
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