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# Copyright (c) 2015 Egor Tensin <Egor.Tensin@gmail.com>
# This file is part of the "Simple interpreter" project.
# For details, see https://github.com/egor-tensin/simple-interpreter.
# Distributed under the MIT License.
class ProgramNode:
def __init__(self, stmt_list):
self._stmt_list = stmt_list
def execute(self):
for stmt in self._stmt_list:
stmt.execute()
_varmap = { }
class CompoundStatementNode:
def __init__(self, stmt_list):
self._stmt_list = stmt_list
def execute(self):
for stmt in self._stmt_list:
stmt.execute()
class EmptyStatementNode:
def execute(self):
pass
class AssignmentNode:
def __init__(self, identifier, arithm_expr):
self._identifier = identifier
self._arithm_expr = arithm_expr
def execute(self):
_varmap[str(self._identifier)] = self._arithm_expr.execute()
return None
class PrintStatementNode:
def __init__(self, arithm_expr):
self._arithm_expr = arithm_expr
def execute(self):
print(self._arithm_expr.execute())
return None
class IdentifierNode:
def __init__(self, identifier):
self._identifier = identifier
def execute(self):
return _varmap[str(self._identifier)]
class AdditionOpNode:
def __init__(self, left, right):
self._left = left
self._right = right
def execute(self):
return self._left.execute() + self._right.execute()
class SubtractionOpNode:
def __init__(self, left, right):
self._left = left
self._right = right
def execute(self):
return self._left.execute() + self._right.execute()
class MultiplicationOpNode:
def __init__(self, left, right):
self._left = left
self._right = right
def execute(self):
return self._left.execute() * self._right.execute()
class DivisionOpNode:
def __init__(self, left, right):
self._left = left
self._right = right
def execute(self):
return self._left.execute() / self._right.execute()
class IntegerNumberNode:
def __init__(self, n):
self._n = n
def execute(self):
return int(self._n)
class FloatingPointNumberNode:
def __init__(self, n):
self._n = n
def execute(self):
return float(self._n)
class IfStatementNode:
def __init__(self, cond, body):
self._cond = cond
self._body = body
def execute(self):
if self._cond.execute():
return self._body.execute()
class TrueNode:
def execute(self):
return True
class FalseNode:
def execute(self):
return False
class AndOpNode:
def __init__(self, left, right):
self._left = left
self._right = right
def execute(self):
return self._left.execute() and self._right.execute()
class OrOpNode:
def __init__(self, left, right):
self._left = left
self._right = right
def execute(self):
return self._left.execute() or self._right.execute()
class EqualsOpNode:
def __init__(self, left, right):
self._left = left
self._right = right
def execute(self):
return self._left.execute() == self._right.execute()
class NotEqualsOpNode:
def __init__(self, left, right):
self._left = left
self._right = right
def execute(self):
return self._left.execute() != self._right.execute()
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