private function setBaseEval($fieldDefinition, $overrides)
    {
        if ($this->isAllowedValue('isunique')) {
            $fieldDefinition['eval']['unique'] = (bool) $this->getOverrideValue('isunique', $overrides);
        }

        foreach (array(
            'tl_class',
            'mandatory',
            'alwaysSave',
            'chosen',
            'allowHtml',
            'preserveTags',
            'decodeEntities',
            'rte',
            'rows',
            'cols',
            'spaceToUnderscore',
            'includeBlankOption',
            'submitOnChange',
            'readonly'
        ) as $name) {
            if (empty($fieldDefinition['eval'][$name])
                && ($value = $this->getOverrideValue($name, $overrides))
            ) {
                $fieldDefinition['eval'][$name] = $value;
            }
        }

        // If we have unique, enforce mandatory.
        if (!empty($fieldDefinition['eval']['unique'])) {
            $fieldDefinition['eval']['mandatory'] = true;
        }

        return $fieldDefinition;
    }
private function setBaseEval($fieldDefinition, $overrides)
    {
        if ($this->isAllowedValue('isunique')) {
            $fieldDefinition['eval']['unique'] = (bool) $this->getOverrideValue('isunique', $overrides);
        }

        foreach (array(
            'tl_class',
            'mandatory',
            'alwaysSave',
            'chosen',
            'allowHtml',
            'preserveTags',
            'decodeEntities',
            'rte',
            'rows',
            'cols',
            'spaceToUnderscore',
            'includeBlankOption',
            'submitOnChange',
            'readonly'
        ) as $name) {
            if (empty($fieldDefinition['eval'][$name])
                && ($value = $this->getOverrideValue($name, $overrides))
            ) {
                $fieldDefinition['eval'][$name] = $value;
            }
        }

        // If we have unique, enforce mandatory.
        if (!empty($fieldDefinition['eval']['unique'])) {
            $fieldDefinition['eval']['mandatory'] = true;
        }

        return $fieldDefinition;
    }
Extract an override value.

@param array $fieldDefinition The field definition.

@param array $overrides       The overrides containing the values to be overridden.

@return array