php man page for filter_has_var

FILTER_HAS_VAR(3)							 1							 FILTER_HAS_VAR(3)

filter_has_var - Checks if variable of specified type exists

SYNOPSIS
       bool filter_has_var (int  $type, string	$variable_name)

DESCRIPTION
PARAMETERS
	      o $type
		- One of INPUT_GET, INPUT_POST, INPUT_COOKIE, INPUT_SERVER, or INPUT_ENV.

	      o $variable_name
		- Name of a variable to check.

RETURN VALUES
	Returns TRUE on success or FALSE on failure.

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