74 lines
1.2 KiB
PHP
74 lines
1.2 KiB
PHP
<?php
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namespace PhpOffice\PhpSpreadsheet\Calculation\Engine;
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class CyclicReferenceStack
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{
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/**
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* The call stack for calculated cells.
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*
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* @var mixed[]
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*/
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private $stack = [];
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/**
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* Return the number of entries on the stack.
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*
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* @return int
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*/
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public function count()
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{
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return count($this->stack);
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}
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/**
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* Push a new entry onto the stack.
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*
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* @param mixed $value
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*/
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public function push($value): void
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{
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$this->stack[$value] = $value;
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}
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/**
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* Pop the last entry from the stack.
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*
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* @return mixed
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*/
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public function pop()
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{
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return array_pop($this->stack);
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}
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/**
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* Test to see if a specified entry exists on the stack.
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*
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* @param mixed $value The value to test
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*
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* @return bool
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*/
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public function onStack($value)
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{
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return isset($this->stack[$value]);
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}
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/**
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* Clear the stack.
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*/
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public function clear(): void
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{
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$this->stack = [];
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}
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/**
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* Return an array of all entries on the stack.
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*
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* @return mixed[]
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*/
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public function showStack()
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{
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return $this->stack;
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}
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}
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