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In PHP, what does “<<<” represent?
Reference - What does this symbol mean in PHP?
can anyone explain me what means those chars? belowe variable contains string:
$txt = <<<EOD
this is simple string
EOD;
$x = ...
can I change <<< for ' ?
It is called here-document.
For general info:
en.wikipedia.org/wiki/Here_document
For php specific info:
http://php.net/manual/en/language.types.string.php
And it is NOT the same as '...'
It's what is called a heredoc.
Heredoc
A third way to delimit strings is the heredoc syntax: <<<. After this operator, an identifier is provided, then a newline. The string itself follows, and then the same identifier again to close the quotation.
The closing identifier must begin in the first column of the line. Also, the identifier must follow the same naming rules as any other label in PHP: it must contain only alphanumeric characters and underscores, and must start with a non-digit character or underscore.
Reference: http://www.php.net/manual/en/language.types.string.php#language.types.string.syntax.heredoc