swift - How to create Dictionary that can hold anything in Key? or all the possible type it capable to hold -


i want create dictionary not limit key type (like nsdictionary)

so tried

var dict = dictionary<any, int>()

and 

var dict = dictionary<anyobject, int>()

resulting

error: type 'any' not conform protocol 'hashable' var dict = dictionary<any, int>()            ^ <repl>:5:12: error: cannot convert expression's type '<<error type>>' type '$t1' var dict = dictionary<any, int>()            ^~~~~~~~~~~~~~~~~~~~~~

ok, use hashable

var dict = dictionary<hashable, int>()

but

error: type 'hashable' not conform protocol 'equatable' var dict = dictionary<hashable, int>()            ^ swift.equatable:2:8: note: '==' requirement refers 'self' type   func ==(lhs: self, rhs: self) -> bool        ^ swift.hashable:1:10: note: type 'hashable' not conform inherited protocol 'equatable.protocol' protocol hashable : equatable          ^ <repl>:5:12: error: cannot convert expression's type '<<error type>>' type '$t1' var dict = dictionary<hashable, int>()            ^~~~~~~~~~~~~~~~~~~~~~~~~~~

so hashable inherited equatable not conform equatable??? don't understand...

anyway, keep trying

typealias keytype = protocol<hashable, equatable> // keytype both hashable , equatable var dict = dictionary<keytype, int>() // happy?

with no luck

error: type 'keytype' not conform protocol 'equatable' var dict = dictionary<keytype, int>()            ^ swift.equatable:2:8: note: '==' requirement refers 'self' type   func ==(lhs: self, rhs: self) -> bool        ^ swift.hashable:1:10: note: type 'keytype' not conform inherited protocol 'equatable.protocol' protocol hashable : equatable          ^ <repl>:6:12: error: cannot convert expression's type '<<error type>>' type '$t1' var dict = dictionary<keytype, int>()            ^~~~~~~~~~~~~~~~~~~~~~~~~~

i lost now, how can make compiler happy code?

i want use dictionary like

var dict = dictionary<any, int>() dict[1] = 2 dict["key"] = 3 dict[someenum.somevalue] = 4

i know can use dictionary<nsobject, int>, not want.

swift 3 update

you can use anyhashable type-erased hashable value, created scenarios this:

var dict = dictionary<anyhashable, int>()


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