$ In php represents a variable, but how can I know the type of this variable?

$ In php represents a variable, but how can I know the type of this variable? & Nbsp; $ in php represents a variable, but how can I know the type of this variable? Share the $ variable in php, but how can I know the type of the variable?
$ In php represents a variable, but how can I know the type of this variable? Share:
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PHP provides six functions (boolean is_int (mixed variable), boolean is_float (mixed variable), boolean is_bool (mixed variable), and boolean is_string (mixed variable), boolean is_array (mixed variable), boolean is_object (mixed variable ))
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In fact, we should be more concerned about how the c parser knows what type?
I have participated in Baidu's interview. after the first round, I had a question in the second round: How do I know an array php parser?