<?php
define('FOOBAR', 'BAZ');
 
$funcao_nativa = 'constant';
 
$funcao_anonima = function ($nome) {
    return $nome;
};
 
//não funciona -> $funcao_nativa (emite WARNING)
echo "Olá {$funcao_nativa(FOOBAR)}\n";
 
//funciona -> $funcao_nativa
echo "Olá {$funcao_nativa('FOOBAR')}\n";
 
//não funciona -> $funcao_anonima e sem apostrofos
echo "Olá {$funcao_anonima(FOOBAR)}\n";
 
//funciona -> $funcao_anonima (não emite WARNING)
echo "Olá {$funcao_anonima('FOOBAR')}\n";

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