Are PHP Variables passed by value or by reference?

Are PHP Variables passed by value or by reference?

php variables pass-by-reference pass-by-value

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In PHP (>= 5.0), is passing by reference faster?

php performance pass-by-reference

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Call-time pass-by-reference has been removed [duplicate]

php class function pass-by-reference public

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How to make a copy of an object without reference?

php object pass-by-reference

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When to pass-by-reference in PHP

php pass-by-reference

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PHP: variable-length argument list by reference?

php pass-by-reference parameter-passing variadic-functions function-parameter

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How do you pass objects by reference in PHP 5?

php variables object pass-by-reference

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PHP: "... variables can be passed by reference" in str_replace()?

php pass-by-reference str-replace

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Laravel 5 getting ID from URL

php database laravel-5 pass-by-reference

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Testing optional arguments in PHP

php pass-by-reference default-value optional-parameters

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how to pass unlimited arguments by reference in php [duplicate]

php function variables arguments pass-by-reference

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PHP: Only variables can be passed by reference

php pass-by-reference

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PHP: check if object/array is a reference

php arrays reference pass-by-reference

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PHP by-reference parameters and default null

php null pass-by-reference

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How can arguments to variadic functions be passed by reference in PHP?

php pass-by-reference variadic-functions

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