87 lines
1.6 KiB
PHP
87 lines
1.6 KiB
PHP
<?php
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namespace Phabel;
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/**
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* Represent variables currently in scope.
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*/
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class VariableContext
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{
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/**
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* Variable list.
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*
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* @var array<string, true>
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*/
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private array $variables;
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/**
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* Custom variable counter.
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*/
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private int $counter = 0;
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/**
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* Constructor.
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*
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* @param array<string, true> $variables Initial variables
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*/
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public function __construct(array $variables = [])
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{
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$this->variables = $variables;
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}
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/**
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* Add variable.
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*
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* @param string $var Variable
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*
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* @return void
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*/
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public function addVar(string $var): void
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{
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$this->variables[$var] = true;
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}
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/**
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* Add variables.
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*
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* @param array<string, true> $vars Variables
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*
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* @return void
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*/
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public function addVars(array $vars): void
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{
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$this->variables += $vars;
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}
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/**
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* Remove variable.
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*
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* @param string $var Variable name
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*
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* @return void
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*/
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public function removeVar(string $var): void
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{
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unset($this->variables[$var]);
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}
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/**
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* Check if variable is present.
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*
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* @param string $var
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* @return boolean
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*/
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public function hasVar(string $var): bool
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{
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return isset($this->variables[$var]);
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}
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/**
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* Get unused variable name.
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*
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* @return string
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*/
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public function getVar(): string
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{
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do {
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$var = 'phabel'.$this->counter;
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$this->counter++;
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} while (isset($this->variables[$var]));
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$this->variables[$var] = true;
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return $var;
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}
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}
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