Framework EDI Reference. SEFManager Utility
.SEMREFS Section

This topic:

• Overview
• The Semantic Rule Syntax
  • The Conditional Clause
  • Multiple Conditional Clause
  • The Action Statement
• Determining the Value
• Value Comparisons
• Existence and Non-Existence

Overview

The .SEMREFS section lists all semantic rules in the SEF file, each showing the semantic object that it is attached to.  The semantic objects can be a data segment, composite element or data element that are used within the context of an ASC/X12 Transaction Set or UN/EDIFACT Message.  The state of these semantic objects can dynamically change depending on how the semantic rule that is attached to the object is satisfied.

For an example in ASC/X12, if the following semantic rule states:

if element 309 in segment TAX at 070 is equal to "M" then segment CTP at 090 must be used

The semantic object that is affected by the semantic rule is clearly "segment CTP at 090".  The semantic object  is attached to the semantic rule and, regardless of what the default state is of the semantic object, if the condition "element 309 in segment TAX at 070 is equal to M" is satisfied then the semantic object "segment CTP at 090" inherits the state "must be used".

In the .SEMREFS section, the semantic rule may be represented as follows:

850/8///=[TaxVar'EQ'M:USAGE:0:]

Where:

• "850/8///" is the location of the semantic object that is dependent on the semantic rule.  This semantic object is data segment CTP at position 090 in the ASC/X12 Transaction Set.  For additional information on object location refer to Appendix A: Object Location.
• "[TaxVar'EQ'M:USAGE:0:]" is the semantic rule.

The Semantic Rule Syntax

The syntax of the semantic rule consists of:

1. A condition clause statement.
2. An action statement.

The form of the entire semantic rule syntax:

• <semantic rule> := <conditional clause> ":" <action statement>
• <conditional clause> := <logical statement> [ "&" | "|" <conditional clause>]
• <logical statement> := <object variable> <operator> <literal value>
• <action statement> := <setting action> | <external routine action>
• <setting action> := <type> ":" <setting> ":"
• <external routine action> := <exit name> ":" <external program> ":" <parameters>
• <external program> := <program name> "." <function>

The Conditional Clause

The conditional clause is made up of a series of logical statements, the result, if true, would invoke the action statement.   A single logical statement follows the syntax:

logical statement := <Object Variable> <Operator> <Literal Value>

Where:

• Object Variable is an object variable that references an object in the SEF.  The object could be a data segment, a composite element or a data element.
• Operator is one of the following, in quotes.
  • 'EXISTS' - Data exists in the object referenced by the Object Variable.
  • 'NEXIST' - Data does not exist in the object referenced by the Object Variable.
  • 'EQ' - Data referenced by the Object Variable is equal to the value.
  • 'NE' - Data referenced by the Object Variable is not equal to the value.
  • 'GT' - Data referenced by the Object Variable is greater than the value.
  • 'GE' - Data referenced by the Object Variable is greater than or equal to the value.
  • 'LT' - Data referenced by the Object Variable is less than the value.
  • 'LE' - Data referenced by the Object Variable is less than or equal to the value.
• Literal Value is any value.

Using the example above, the following condition of the semantic rule states that the value referenced by the object variable "TaxVar" is equal to the literal value "M".

TaxVar'EQ'M

Where:

• "TaxVar" is the object variable that is attached to element 309 in segment TAX at 070.
• 'EQ' is the equal to operator.
• "M" is the literal value.

Multiple Conditional Clause

If multiple logical statements are required in the conditional clause then they are separated by the "&" or "|" boolean type operator for "AND" or "OR" respectively.

<conditional clause> := <logical statement> [ "&" | "|" <conditional clause>]

For example,

TaxVar'EQ'M|CurVar'EQ'U&RefVar'NE'ABC

which means: TaxVar is equal to "M" OR CurVar is equal to "U" AND RefVar is not equal to "ABC".  In a semantic rule, the conditional clause always precedes the action statement.

TaxVar'EQ'M|CurVar'EQ'U&RefVar'NE'ABC:USAGE:0:

The Action Statement

The action statement indicates what action to take if the result of the conditional clause is true.  Currently, only the following types of actions are possible:

• USAGE. Dynamically set the user requirement of a data segment, composite element or data element to the following:
  

  CODE	DESCRIPTION
  0	Used
  1	Not Used
  2	Must Use
  3	Recommended
  4	Not Recommended

 

Syntax:

<type> ":" <setting> ":"

Where

• <type> is USAGE and,
•  <setting> is one of the code specified in the table above: 0,1,2,3,4.

For example (note the trailing colon),

850/8///=TaxVar'EQ'M:USAGE:2:

Which means: if the object variable TaxVar is equal to M then the segment CTP090 must be used.  In this example, the location 850/8/// points to data segment CTP090.


• LOCALCODE.  Enable the data element to use a set of codes if the condition is met.
  
  Syntax:

  <type> ":" <setting> ":"
  
  Where

  • <type> is LOCALCODE and,
  • <setting> is the code set ordinal specifying the list of codes.

  For example (note the trailing colon),

  850/2///1=TaxVar'EQ'M:LOCALCODE:3:

  Which means: if the object variable TaxVar is equal to M then the data element 353 must use the code set at ordinal 3.  In this example, the location 850/2///1 points to data element 353.
  

• APPVALUE.  Redirect the data element to use a different list of values.
  
  Syntax:

  <type> ":" <setting> ":"
  
  Where

  • <type> is APPVALUE and,
  • <setting> is the name of the value list.
    

  For example (note the trailing colon),

  850/47///2=TaxVar'EQ'M:APPVALUE:NAMES:

  Which means: if the object variable TaxVar is equal to M then the data element 93 must use the value list NAMES.  In this example, the location 850/47///2 points to data element 93.
  

• COMEXIT.  Run an ActiveX/COM component.  Other exit names are allowed in the SEF standard, but the SEFManager only allows COMEXIT type executable routines, which are ActiveX/COM components only.

The program name is the program identifier of the interface and the method name to execute, followed by any parameters.

"COMEXIT" ":" <program name> ":" <parameters>

Example,

COMEXIT:FrediTester.Sample.Test:1,2,3,ABC

Where:

• "COMEXIT" is the exit name for the type.
• "FrediTester.Sample.Test" is the program name, which consists of the program identifier "FrediTester.Sample" and the method name to execute "Test".
• "1,2,3,ABC" is the parameter to pass to the routine.

Determining the Value

The value of a semantic object is captured by an object variable that is attached to semantic object.  The object variable contains a variable name and the location of the object in the implementation guideline.  The value resolved in the object variable is determined by locating the corresponding object in the document and extracting the data.  This value is then used to compare to the literal value in the conditional expression of the semantic rule.  The value determined for each of the semantic object is as follows:

• Data Element - The value of the data element.
• Composite Element - The value of all sub elements separated by the composite delimiter.
• Data Segment - The value of all the data elements and composite elements separated by their delimiters.

Value Comparisons

When the value in the object variable is compared with the literal value, it either does a string comparison or a numeric comparison.  A string comparison compares the a character in the first value to its corresponding character in the second value in the string starting with the leftmost character.  In a string comparison, the string value "04" is greater than the string value "004".  In a numeric comparison, the numeric value of both string values are compared.  In this case, the value "04" is equal to the value "004".  The inherent nature of data retrieved from the document is always a string, and if a numeric comparison is involved then a string to numeric conversion must takes place.  For a successful numeric conversion, the string must contain only numeric values (0 to 9), but it is possible that a string containing alphabetic character can be involved in the conversion.  If this is the case, starting from the left, a string is converted to a number character by character until a non-numeric character is encountered.  For example, the string "123.1B2" is converted to 123.1; the string "12B3" to 12; the string "B123" to zero; etc.  Note how the alphabet "B" stops the conversion.

The values in the conditional clause are compared depending on the semantic object:

• Data Element.  The value determined in the object variable, that references a data element, is compared to the literal value according to the data type of the data element.  The comparison is numeric if the data type of the data element is "Nx" or "R" in ASC/X12 or "Nx" in UN/EDIFACT; it is a string comparison otherwise.
• Composite Element.  A string comparison is made on the entire composite element string to the literal value, including the delimiter.
• Data Segment.  A string comparison is made on the entire data segment string to the literal value, including the delimiter.

Existence and Non-Existence

The semantic rule also tests for the existence or non-existence of a semantic object.  This is the case when the operator "exists" or "does not exist" is present in the conditional clause of the semantic rule.  For example,

if data segment REF04 exists then segment MEA must be used

if data segment SAC07 does not exist then segment FOB is not used

The existence or non-existence of an object is interpreted as follows:

• Data Element
  • Exists if the length of the data is greater than zero.
  • Does not exist if it contains empty data (length of the data is zero), or if the data element is in a data segment that does not exist.
• Composite Element
  • Exists if any of the sub element contain data.
  • Does not exist if none of its sub element contain data, or the composite element is in a data segment that does not exist.
• Data Segment
  • Exists if any of its composite element or data element contain data.
  • Does not exist if data segment is not in the document, or if none of its composite element or data element contain data.  A data segment will also test as not existing if there is a forward reference to it in the semantic rule.  That is, the semantic rule is being calculated but the data segment has not yet been encountered and resolved while processing the document.  Data segments are processed sequentially in order of their occurrence in the document.

See Also

• Standard Exchange Format (SEF)
• Creating a Semantic Rule Syntax