php:: apply backticks to first word in sentence

basically what I am trying to do is,

I have an array that looks something like this:

array(
  a开发者_开发知识库rray(
    'select' =>'first string',
    'escape' => true
  ),
  array(
    'select' =>'second',
    'escape' => true
  ),
  array(
    'select' =>'the third string',
    'escape' => true
  ),
  array(
    'select' =>'fourth string',
    'escape' => false
  ),
)

I am looping over it and I want to end up with this output

array(
  array(
    'select' =>'`first` string',
    'escape' => true
  ),
  array(
    'select' =>'`second`',
    'escape' => true
  ),
  array(
    'select' =>'`the` third string',
    'escape' => true
  ),
  array(
    'select' =>'fourth string',
    'escape' => false
  ),
)

so basic rules are

• backticks are only applied if escape is true
• backticks are only applied to the first word in a sentence
• if there is only one word backticks are applied to the word

My plan was to use

if($item['escape']) {
  $pos = (strpos($item['select'], ' ') === false ? strlen($item['select']) : strpos($item['select'], ' '));
  $item['select'] = '`' . substr($item['select'], 0, $pos) . '`' . substr($item['select'], $pos, strlen($item['select']));
}

but the $item['select'] = line seems rather long winded, is there a better way to write it?

if($item['escape']) {
    $item['select'] = explode(' ', $item['select']);
    $item['select'][0] = '`'.$item['select'][0].'`';
    $item['select'] = implode(' ', $item['select']);
}

should be good.

You could split $item['select'] on the space character:

if($item['escape']) {
  $words = explode(' ', $item['select']);
  $words[0] = "`{$words[0]}`";
  $item['select'] = implode(' ', $words);
}

How about a regular expression?

$item['select'] = preg_replace( '/^(.*?)( |\z)(.*)/', '`$1`$2$3' , $item['select']);

It's short and its intent clear.

Edited: didn't take into account the case where there is only one word (it doesn't look very simple now...)

You can use regex as:

foreach($input as $key => &$val) {
        if($val['escape']) {
                $val['select'] = preg_replace('/^(\w+)/','`$1`',$val['select']);
        }
}

See it