ethereum.forks.tangerine_whistle.vm.stack

Ethereum Virtual Machine (EVM) Stack.

.. contents:: Table of Contents :backlinks: none :local:

Introduction

Implementation of the stack operators for the EVM.

pop

Pops the top item off of stack.

Parameters

stack : EVM stack.

Returns

value : U256 The top element on the stack.

def pop(​stack: List[U256]​) -> U256:
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    """
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    Pops the top item off of `stack`.
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    Parameters
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    ----------
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    stack :
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        EVM stack.
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    Returns
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    -------
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    value : `U256`
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        The top element on the stack.
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    """
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    if len(stack) == 0:
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        raise StackUnderflowError
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    return stack.pop()

push

Pushes value onto stack.

Parameters

stack : EVM stack.

value : Item to be pushed onto stack.

def push(​stack: List[U256], ​​value: U256​) -> None:
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    """
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    Pushes `value` onto `stack`.
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    Parameters
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    ----------
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    stack :
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        EVM stack.
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    value :
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        Item to be pushed onto `stack`.
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    """
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    if len(stack) == 1024:
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        raise StackOverflowError
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    return stack.append(value)