lib

type ListMapper interface {

	// Len() returns the length of the list
	// The length is only increased by Push() and not decreased
	// ListMapper dosen't check if an index is in bounds
	// The user should check Len() before doing any actions
	Len(sdk.Context) uint64

	// Get() returns the element by its index
	Get(sdk.Context, uint64, interface{}) error

	// Set() stores the element to the given position
	// Setting element out of range will break length counting
	// Use Push() instead of Set() to append a new element
	Set(sdk.Context, uint64, interface{})

	// Delete() deletes the element in the given position
	// Other elements' indices are preserved after deletion
	// Panics when the index is out of range
	Delete(sdk.Context, uint64)

	// Push() inserts the element to the end of the list
	// It will increase the length when it is called
	Push(sdk.Context, interface{})

	// CONTRACT: No writes may happen within a domain while iterating over it.
	IterateRead(sdk.Context, interface{}, func(sdk.Context, uint64) bool)

	// IterateWrite() is safe to write over the domain
	IterateWrite(sdk.Context, interface{}, func(sdk.Context, uint64) bool)

	// Key for the length of the list
	LengthKey() []byte

	// Key for getting elements
	ElemKey(uint64) []byte
}

type Mapper struct {
	// contains filtered or unexported fields
}

type QueueMapper interface {
	// Push() inserts the elements to the rear of the queue
	Push(sdk.Context, interface{})

	// Peek() returns the element at the front of the queue without removing it
	Peek(sdk.Context, interface{}) error

	// Pop() returns the element at the front of the queue and removes it
	Pop(sdk.Context)

	// IsEmpty() checks if the queue is empty
	IsEmpty(sdk.Context) bool

	// Flush() removes elements it processed
	// Return true in the continuation to break
	// The interface{} is unmarshalled before the continuation is called
	// Starts from the top(head) of the queue
	// CONTRACT: Pop() or Push() should not be performed while flushing
	Flush(sdk.Context, interface{}, func(sdk.Context) bool)

	// Key for the index of top element
	TopKey() []byte
}