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Message-ID: <445A5840.2050000@vocalspace.com>
Date: Thu, 04 May 2006 14:38:40 -0500
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To: "D. Dante Lorenso" <dante@vocalspace.com>
Cc: dante@lorenso.com, internals@lists.php.net
References: <44584619.60400@lorenso.com> <44591E27.4030005@vocalspace.com>
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Subject: Re: [PHP-DEV] Specification for function filled() :: was ifsetor/coalesce
From: dante@vocalspace.com ("D. Dante Lorenso")

The default value for 'filled()' if all values test TRUE for empty() 
should be FALSE, not NULL.  This is more consistent with the return 
values of empty().

Since filled() returns the first non-empty() value in the list of 
parameters provided, it works well when cast into a boolean context 
because the non-empty() value should evaluate as TRUE.  Example:

    filled("testing") // returns testing
    if (filled("testing")) {} // true
    filled(87) // returns 87
    (boolean) filled(87) // true

    $x["apple"] = "42";
    filled($x["apple"]) // returns 42
    filled($x["pear"]) // returns false
    if (filled($x["apple"]) !== false) {} // true
    if (filled($x["pear"]) !== false) {} // false

Just wanted to chime in with an update in case 'filled()' can actually 
be considered.  I'd like everyone to consider this one function to be 
evaluated on it's merits alone and apart from any other functions which 
also might be wanted.  filled() is the opposite of empty() and is not 
dealing with tests for 'isset()'.  Another function should be proposed 
to solve that problem if it would still be needed after filled() is 
implemented.

Do I have any power to call a vote on this?

Dante


D. Dante Lorenso wrote:
> Dear Internals,
>
> I'd like a white bikeshed, but until you can decide on a color, how 
> about we just build the bikeshed already.  Please consider the 
> following specification:
>
> ========== 8< ==================== 8< ==================== 8< ==========
>
> filled
>
> (PHP 5.2.0)
>
> filled - Find first non-empty value in a variable list where empty() 
> evaluates as FALSE.
>
> Description
> ------------------------------
>
> mixed filled ( mixed varname [, mixed ...] )
>
> filled() takes a variable number of parameters.  For each of these, 
> *filled()* looks for a variable where !empty( varname ) evaluates as 
> TRUE.  It returns the first non-empty value or NULL if all values are 
> empty().
>
> Note: filled() only checks variables as anything else will result in a 
> parse error.  In other words, the following will not work: 
> filled(trim($name)).
>    filled() is the opposite of empty(), and no warning is generated 
> when any one of the variables is not set.
>
> Return Values
> ------------------------------
>
> Returns first non-empty() value.
>
> If all values are empty(), returns NULL.
>
> Example
> ------------------------------
> <?php
> echo filled($x["somekey"], $_GET["getkey"], $default, "example");
> echo filled("yes"); // prints yes
> filled(false); // returns NULL
> echo filled($x["apple"], $y, "banana"); // prints banana
> $y = "cat";
> echo filled($x["apple"], $y, "banana"); // prints cat
> $x["apple"] = "pear";
> echo filled($x["apple"], $y, "banana"); // prints pear
> unset($x["apple"]);
> echo filled($x["apple"], $y, "banana"); // prints cat
> ?>
>
> See also empty()
>
> ========== 8< ==================== 8< ==================== 8< ==========
>
> Dante
>