- var_dump: documentation ( source)
<?php
$formatter = \NumberFormatter::create(\Locale::getDefault(), \NumberFormatter::DECIMAL);
var_dump($formatter->getTextAttribute(\NumberFormatter::POSITIVE_PREFIX));
var_dump($formatter->getTextAttribute(\NumberFormatter::NEGATIVE_PREFIX));
$formatter->setTextAttribute(\NumberFormatter::POSITIVE_PREFIX, $formatter->getSymbol(\NumberFormatter::PLUS_SIGN_SYMBOL));
var_dump($formatter->format(12));
var_dump($formatter->format(-12));
var_dump($formatter->format(12.5));
var_dump($formatter->format(0));
var_dump($formatter->format(-0));