HASSLE Code documentation

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Chapter 4: Layers

Layers

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$Header: /bioy2/biocomputing/eggenber/Hassle/RCS/spec.txt,v 1.16 1994/06/15 14:04:09 eggenber Exp $ /* Type: communication */

The HASSLE code has several elements, and several layers. The purpose of this is to 

 
            allow for a structured API
  
            generate areas for independent code development
  
            allow for applications other than HASSLE to speak 
  
                     the HASSLE protocol
  
            allow a layered software verification.
As shown in figure \ref {figure_layer}, each of the layers can be accessed by the HASSLE API. On the service layer, both client and server modules have access to the API.

An important feature of HASSLE is that the variables needed for communication amongst the different modules are kept local, in order to avoid global variables. Therefore, in addition to utilities on each layer, vertical utilities allow to access variables across the whole code. Other typical features of the vertical utilities are explained below.

The Verification of HASSLE is performed using the HASSLE API and a special function built into the code which allows each important branchpoint to be triggered in specific fashion. The use of the HASSLE API for this purpose serves as verification as well, both with respect to documentation and reliability. Figure \ref {figure_verify} on shows the systematic analysis of HASSLE code using the layered structure of the code.

Section 4.1: Command layer

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    Command-line processing
  
    Process control
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