array_map() with multiple callback functions

[George Langley]

Hi all. I want to apply strtolower() AND trim() to all items in an array. But I don't see a way to call multiple callbacks with the array_map() function.
Are my two choices the following:

// 1) nesting two array_map() calls
$cleanData = array_map('trim',(array_map('strtolower',$rawData)));


// 2) call my own function with array_walk()
$cleanData = array_walk('myCleaner',$rawData);

function myCleaner($passedData){
$cleanData = array_map('strtolower',$passedData);
$cleanData = array_map('trim',$cleanData);
}
//(Of course, wouldn't bother with a function, just to call array_map twice...)

Just seeing if there's a better way than having to go through the array twice to apply each callback separately. Thanks,

[Alex Nikitin]

Something like:

$cleanData = array_map(function($str){return strtolower(trim($str));},
$passedData);
--
The trouble with programmers is that you can never tell what a
programmer is doing until it’s too late. ~Seymour Cray

Post by George Langley
Hi all. I want to apply strtolower() AND trim() to all items in an array. But I don't see a way to call multiple callbacks with the array_map() function.
// 1) nesting two array_map() calls
$cleanData = array_map('trim',(array_map('strtolower',$rawData)));
// 2) call my own function with array_walk()
$cleanData = array_walk('myCleaner',$rawData);
function myCleaner($passedData){
$cleanData = array_map('strtolower',$passedData);
$cleanData = array_map('trim',$cleanData);
}
//(Of course, wouldn't bother with a function, just to call array_map twice...)
Just seeing if there's a better way than having to go through the array twice to apply each callback separately. Thanks,
--
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[Andrew Ballard]

Post by Alex Nikitin

Post by George Langley
Hi all. I want to apply strtolower() AND trim() to all items in an array. But I don't see a way to call multiple callbacks with the array_map() function.
// 1) nesting two array_map() calls
$cleanData = array_map('trim',(array_map('strtolower',$rawData)));
// 2) call my own function with array_walk()
$cleanData = array_walk('myCleaner',$rawData);
function myCleaner($passedData){
$cleanData = array_map('strtolower',$passedData);
$cleanData = array_map('trim',$cleanData);
}
//(Of course, wouldn't bother with a function, just to call array_map twice...)
Just seeing if there's a better way than having to go through the array twice to apply each callback separately. Thanks,

$cleanData = array_map(function($str){return strtolower(trim($str));},
$passedData);

I'd go with this general approach, whether you use a named function or
an anonymous function for the callback. I don't know how large the
array is, but option #1 iterates the input array twice and option #2
iterates the array three times. If you eventually need to add
additional functions to clean the input, they would add even more
iterations. This approach only iterates once.

Andrew

[Jim Giner]

Post by George Langley
Hi all. I want to apply strtolower() AND trim() to all items in an array. But I don't see a way to call multiple callbacks with the array_map() function.
// 1) nesting two array_map() calls
$cleanData = array_map('trim',(array_map('strtolower',$rawData)));
// 2) call my own function with array_walk()
$cleanData = array_walk('myCleaner',$rawData);
function myCleaner($passedData){
$cleanData = array_map('strtolower',$passedData);
$cleanData = array_map('trim',$cleanData);
}
//(Of course, wouldn't bother with a function, just to call array_map twice...)
Just seeing if there's a better way than having to go through the array twice to apply each callback separately. Thanks,

Not sure if you have an answer to this yet, so I'll present my simpler
approach.

foreach ($my_array as &$v)
{
$v = trim($v);
$v = strtolower($v);
}

[George Langley]

Post by George Langley
Hi all. I want to apply strtolower() AND trim() to all items in an array. But I don't see a way to call multiple callbacks with the array_map() function.
// 1) nesting two array_map() calls
$cleanData = array_map('trim',(array_map('strtolower',$rawData)));
// 2) call my own function with array_walk()
$cleanData = array_walk('myCleaner',$rawData);
function myCleaner($passedData){
$cleanData = array_map('strtolower',$passedData);
$cleanData = array_map('trim',$cleanData);
}
//(Of course, wouldn't bother with a function, just to call array_map twice...)
Just seeing if there's a better way than having to go through the array twice to apply each callback separately. Thanks,

Not sure if you have an answer to this yet, so I'll present my simpler approach.
foreach ($my_array as &$v)
{
$v = trim($v);
$v = strtolower($v);
}
--
$cleanData = array_map(function($str){return strtolower(trim($str));},
$passedData);

------
Thanks guys - will check both out to see what works best in my situation.

George