StringyHash - easy to use hash

[Petr Schreiber]

The latest thinBasic, 1.9.16.x, contains very powerful, low level hash implementation.
Here is a wrapper, which offers the following improvements:

you can decide whether hash keys are case sensitive or not
automatic garbage collection (no need to worry about freeing the memory)


You can download the unit from the attachement, to get idea about use, checkout this:


Uses "Console"

#INCLUDE "StringHash.tbasicu"

Dim h As stringyHash(4, FALSE)

h.SetKey("Name" , "Darth")
h.SetKey("Surname", "Vader")

PrintL "Initial key count: " + h.CountKeys

If h.hasKey("SurName") Then h.RemoveKey("SURNAME") ' -- Case insensivity allows this

PrintL "Key count after removal of one: " + h.CountKeys

PrintL h.GetKey("Name")

Dim h2 As stringyHash
h2.CloneFrom(h)
PrintL "Key count of cloned hash: " + h2.CountKeys

PrintL h2.GetKey("Name")

WaitKey



Petr

[ErosOlmi]

More information about thinBasic implementation of Hash Tables: http://www.thinbasic.com/public/products/thinBasic/help/html/index.html?hash_table.htm

Hash Tables, or Associative Arrays, are very efficient and ultra fast data structures able to store key/data pairs. More infor at https://en.wikipedia.org/wiki/Hash_table

Their internal implementation is quite complex but their usage if very easy and straight.
To create, store, retrieve, big amount of data you just need a double word variable store anywhere.
Every key/data can store big amount of memory handled as simple dynamic strings.

Examples can be found in thinBasic installation path at \thinBasic\SampleScripts\DataStructures\

As usual Petr find more advanced ways to use thinBasic power :)