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Date: Wed, 7 Jun 2017 22:03:31 +0200
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Subject: preg_match() option for anchored offset?
From: rasmus@mindplay.dk (Rasmus Schultz)

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What do you think about adding another option to preg_match() to allow the
$offset parameter to be treated as the start anchor?

The manual proposes to do this:

    $subject = "abcdef";
    $pattern = '/^def/';
    $offset = 3;
    preg_match($pattern, substr($subject, $offset), $matches);

In other words, use substr() to copy the entire remainder of the string.

I just wrote a simple SQL parser tonight, and had to use this approach,
which (I imagine) must be pretty inefficient?

I'd like to be able to do the following:

    $subject = "abcdef";
    $pattern = '/^def/';
    $offset = 3;
    preg_match($pattern, $subject, $matches, PREG_ANCHOR_OFFSET, $offset);

This new option would make the ^ anchor work from the given $offset, which
allows me to parse the entire $subject without copying anything.

Thoughts?

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