php template function

drop_vars.php

<?php

function drop_vars(string $string, array $vars, array $enclosure = ['{{', '}}'], string $escapeStr = '@'): string
{
    // Escape escapeStr and enclosure
    $escapeStr = preg_quote($escapeStr, '/');
    
    // Escape enclosure phrases
    [$open, $close] = array_map(fn($i) => preg_quote($i, '/'), $enclosure);
    
    // Search vars and replace with value
    return preg_replace_callback("/($escapeStr?)($open\s?([^$open$close]*)\s*$close)/Uis",
        function ($matches) use ($vars) {
            [$original, $escape, $format, $var] = $matches;
            
            // Check if escape return format
            if (!empty($escape)) return $format;
            
            // Trim spaces around var
            $var = trim($var);
            
            // Check if key exists in vars
            if (array_key_exists($var, $vars)) return $vars[$var];
            
            return $format;
        }, $string);
}

$str = <<<STR
Hi, My name is {{first_name}}
and my family name is {{ last_name}},
To sum it up, my name is {{full_name }}.
I am a {{ job_title    }}.
To use my function just write your vars like this @{{code}}
STR;

$vars = [
    'first_name' => 'John',
    'last_name'  => 'Doe',
    'full_name'  => 'John Doe',
    'job_title'  => 'Space Cowboy',
];

echo drop_vars($str, $vars);