php regex: Use quotes for match, but don't capture them - php

Question

I'm unsure if I should be using preg_match, preg_match_all, or preg_split with delim capture. I'm also unsure of the correct regex.
Given the following:
$string = " ok 'that\\'s cool' \"yeah that's \\\"cool\\\"\"";
I want to get an array with the following elems:
[0] = "ok"
[1] = "that\'s"
[2] = "yeah that's \"cool\""

Answer 1

You can not do this with a regular expression because you're trying to parse a non-context-free grammar. Write a parser.
Outline:
read character by character, if you see a \ remember it.
if you see a " or ' check if the previous character was \. You now have your delimiting condition.
record all the tokens in this manner
Your desired result set seems to trim spaces, you also lost a couple of the \s, perhaps this is a mistake but it can be important.
I would expect:
[0] = " ok " // <-- spaces here
[1] = "that\\'s cool"
[2] = " \"yeah that's \\\"cool\\\"\"" // leading space here, and \" remains

Answer 2

Actually, you might be surprised to find that you can do this in regex:
preg_match_all("((?|\"((?:\\\\.|[^\"])+)\"|'((?:\\\\.|[^'])+)'|(\w+)))",$string,$m);
The desired result array will be in $m[1].

Answer 3

You can do it with a regex:
$pattern = <<<'LOD'
~
(?J)
# Definitions #
(?(DEFINE)
(?<ens> (?> \\{2} )+ ) # even number of backslashes
(?<sqc> (?> [^\s'\\]++ | \s++ (?!'|$) | \g<ens> | \\ '?+ )+ ) # single quotes content
(?<dqc> (?> [^\s"\\]++ | \s++ (?!"|$) | \g<ens> | \\ "?+ )+ ) # double quotes content
(?<con> (?> [^\s"'\\]++ | \s++ (?!["']|$) | \g<ens> | \\ ["']?+ )+ ) # content
)
# Pattern #
\s*+ (?<res> \g<con>)
| ' \s*+ (?<res> \g<sqc>) \s*+ '?+
| " \s*+ (?<res> \g<dqc>) \s*+ "?+
~x
LOD;
$subject = " ok 'that\\'s cool' \"yeah that's \\\"cool\\\"\"";
preg_match_all($pattern, $subject, $matches, PREG_SET_ORDER);
foreach($matches as $match) {
var_dump($match['res']);
}
I made the choice to trim spaces in all results, then " abcd " will give abcd. This pattern allows all backslashes you want, anywhere you want. If a quoted string is not closed at the end of the string, the end of the string is considered as the closing quote (this is why i have made the closing quotes optional). So, abcd " ef'gh will give you abcd and ef'gh