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phppythonreplacelanguage-comparisons

PHP equivalent of Python's `str.format` method?


Is there an equivalent of Python str.format in PHP?

In Python:

"my {} {} cat".format("red", "fat")

All I see I can do in PHP natively is by naming the entries and using str_replace:

str_replace(array('{attr1}', '{attr2}'), array('red', 'fat'), 'my {attr1} {attr2} cat')

Is there any other PHP's native alternatives?


Solution

  • As PHP doesn't really have a proper alternative to str.format in Python, I decided to implement my very simple own which as most of the basic functionnalitites of the Python's one.

    function format($msg, $vars)
    {
        $vars = (array)$vars;
    
        $msg = preg_replace_callback('#\{\}#', function($r){
            static $i = 0;
            return '{'.($i++).'}';
        }, $msg);
    
        return str_replace(
            array_map(function($k) {
                return '{'.$k.'}';
            }, array_keys($vars)),
    
            array_values($vars),
    
            $msg
        );
    }
    
    # Samples:
    
    # Hello foo and bar
    echo format('Hello {} and {}.', array('foo', 'bar'));
    
    # Hello Mom
    echo format('Hello {}', 'Mom');
    
    # Hello foo, bar and foo
    echo format('Hello {}, {1} and {0}', array('foo', 'bar'));
    
    # I'm not a fool nor a bar
    echo format('I\'m not a {foo} nor a {}', array('foo' => 'fool', 'bar'));
    
    1. The order doesn't matter,
    2. You can omit the name/number if you want it to simply increment (the first {} matched will be transformed into {0}, etc),
    3. You can name your parameters,
    4. You can mix the three other points.