PHP: Variable Handling Functions

1. debug_zval_dump — Dumps a string representation of an internal zend value to output
2. doubleval — Alias of floatval
3. empty — Determine whether a variable is empty
4. floatval — Get float value of a variable
5. get_defined_vars — Returns an array of all defined variables
6. get_resource_type — Returns the resource type
7. gettype — Get the type of a variable
8. import_request_variables — Import GET/POST/Cookie variables into the global scope
9. intval — Get the integer value of a variable
10. is_array — Finds whether a variable is an array
11. is_bool — Finds out whether a variable is a boolean
12. is_callable — Verify that the contents of a variable can be called as a function
13. is_double — Alias of is_float
14. is_float — Finds whether the type of a variable is float
15. is_int — Find whether the type of a variable is integer
16. is_integer — Alias of is_int
17. is_long — Alias of is_int
18. is_null — Finds whether a variable is NULL
19. is_numeric — Finds whether a variable is a number or a numeric string
20. is_object — Finds whether a variable is an object
21. is_real — Alias of is_float
22. is_resource — Finds whether a variable is a resource
23. is_scalar — Finds whether a variable is a scalar
24. is_string — Find whether the type of a variable is string
25. isset — Determine if a variable is set and is not NULL
26. print_r — Prints human-readable information about a variable
27. serialize — Generates a storable representation of a value
28. settype — Set the type of a variable
29. strval — Get string value of a variable
30. unserialize — Creates a PHP value from a stored representation
31. unset — Unset a given variable
32. var_dump — Dumps information about a variable
33. var_export — Outputs or returns a parsable string representation of a variable

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