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# Subspace

`Subspace` is a prefixed subspace of the parameter store. Each module which uses the 
parameter store will take a `Subspace` to isolate permission to access.

## Key

Parameter keys are human readable alphanumeric strings. A parameter for the key 
`"ExampleParameter"` is stored under `[]byte("SubspaceName" + "/" + "ExampleParameter")`, 
	where `"SubspaceName"` is the name of the subspace.

Subkeys are secondary parameter keys those are used along with a primary parameter key.
Subkeys can be used for grouping or dynamic parameter key generation during runtime.

## KeyTable

All of the parameter keys that will be used should be registered at the compile 
time. `KeyTable` is essentially a `map[string]attribute`, where the `string` is a parameter key.

Currently, `attribute` consists of a `reflect.Type`, which indicates the parameter 
type to check that provided key and value are compatible and registered, as well as a function `ValueValidatorFn` to validate values.

Only primary keys have to be registered on the `KeyTable`. Subkeys inherit the 
attribute of the primary key.

## ParamSet

Modules often define parameters as a proto message. The generated struct can implement
`ParamSet` interface to be used with the following methods:

* `KeyTable.RegisterParamSet()`: registers all parameters in the struct
* `Subspace.{Get, Set}ParamSet()`: Get to & Set from the struct

The implementor should be a pointer in order to use `GetParamSet()`.
