The SEDRIS Data Representation Model
APPENDIX A - Classes
Pseudo Code Function

Class Name: Pseudo Code Function

Superclass - <Function>

Subclasses

This DRM class is concrete and has no subclasses.

Definition

An instance of this DRM class specifies the behaviour of a function that does not correspond to a <Predefined Function>.

Primary Page in DRM Diagram:

Secondary Pages in DRM Diagram:

This class appears on only one page of the DRM class diagram.

Example

No Example supplied.

FAQs

Why is <Pseudo Code Function> needed ? Doesn't this leave room for ambiguity?

The decision to support <Pseudo Code Function> was based on three primary concerns. First, we felt that it would be nearly impossible to capture every possible function that would be used to define the behaviour of <Control_Link> instances. Second, <Expression> instances lack the expressive power to define functions that require looping, branching, etc. Finally, given the first two, it is recognized that many functions that are relatively simple when viewed as pseudo code or code fragments, would become overly complicated when converted into an expression tree. It is important to keep in mind, that while any valid <Expression> instances could be converted into executable code or structures that could be directly used by a consuming system, most systems will not use them that way. Currently, the majority of consuming systems would require that the expression be recoded into the consuming system. For complex functions, pseudo code may be easier to convert.

Constraints

Composed of (two-way) (inherited)

Component of (two-way) (inherited)

Inherited Field Elements

EDCS_Attribute_Value_Type value_type; (notes)

Field Elements

SE_String name; (notes)
SE_String pseudo_code; (notes)

Notes

Composed of Notes


Expression

 The <Expression> components of a <Function>, if any,
 represent the arguments of the function being represented, so a
 <Function> has <Expression> components if that
 <Function> takes arguments. The <Expression> components
 are ordered so as to unambiguously specify which <Expression>
 is being supplied for each argument of the given <Function>.
 The exact interpretation of each argument is defined by
 the specific function.

Fields Notes


value_type

 The value_type of a <Function> instance returns the type of value
 produced when the <Function> instance is evaluated for its arguments.

name

 The name field specifies the name of the function being represented.

pseudo_code

 The pseudo_code field specifies the psuedo code describing the
 behaviour of the function represented by the given
 <Pseudo Code Function> instance.
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Last updated: July 16, 2004 Copyright © 2004 SEDRIS™