src/Execution.php
public function setVariableLocal($name, $value)
    {
        if (!$this->isScope()) {
            return $this->getScope()->setVariableLocal($name, $value);
        }
        
        if ($value === null) {
            unset($this->variables[(string) $name]);
        } else {
            $this->variables[(string) $name] = $value;
        }
        
        $this->markModified();
    }
public function setVariableLocal($name, $value)
    {
        if (!$this->isScope()) {
            return $this->getScope()->setVariableLocal($name, $value);
        }
        
        if ($value === null) {
            unset($this->variables[(string) $name]);
        } else {
            $this->variables[(string) $name] = $value;
        }
        
        $this->markModified();
    }
Set the given variable in the current scope, setting a variable to a value of null will
remove the variable from the current scope.

@param string $name
@param mixed $value