PHPda Teskari Chiziq Muammosi

Teskari chiziq PHPning maxsus belgisidir. Bu shuni anglatadiki, qator ichida, agar biz xohlasak, chiziq o'zini anglatishi uchun, biz uni ikki marta takrorlashimiz kerak:

<?php
	$str = '\\ \\\\ \\\\\\'; // aslida qator '\ \\ \\\'
?>

Teskari chiziq shuningdek muntazam ifodalarning ham maxsus belgisidir. Bu shuni anglatadiki, muntazam ifoda ichida, chiziq o'zini anglatishi uchun, uni to'rt marta yozishimiz kerak:

<?php
	echo preg_replace('#\\\\#', '!', '\\ \\\\ \\\\\\'); // chiqadi '! ! !!'
?>

Keling endi shunday muntazam ifoda yozaylik, unda qidiruv shabloni quyidagicha bo'ladi: teskari chiziq bir yoki bir necha marta. Bunday holda biz + operatorini guruhlamasdan oldingi 4 belgi uchun yozamiz:

<?php
	echo preg_replace('#\\\\+#', '!', '\\ \\\\ \\\\\\'); // chiqadi '! ! !'
?>

Berilgan qator:

<?php
	$str = 'a\\b c\\d e\\f';
?>

Ushbu qatordagi barcha pastki qatorlarni shablon bo'yicha toping harf, teskari chiziq, harf.

Berilgan qator:

<?php
	$str = 'a\\b c\\\\d e\\\\\\f';
?>

Ushbu qatordagi barcha pastki qatorlarni shablon bo'yicha toping harf, teskari chiziq istalgan miqdorda, harf.