Using Mapping Services › Type Conversion for MDO Assignment

Type Conversion for MDO Assignment

Normally when assigning data from one MDO component to another the type of each component is identical so that data can be moved unchanged. However, if the target component is not of the same type as the source component type conversion is automatically performed where possible. Hence the result of the following assignment depends on the type of a.b.c and x.y.z:

&ASSIGN MDO=a.b.c FROM MDO=x.y.z

When assigning into an MDO from external data, or from NCL variables the data type of the input can be nominated for the MDO assignment. If the MDO component is not of this type then type conversion is performed, for example:

&ASSIGN MDO=a.b.c TYPE=INTEGER FROM DATA=123

&ASSIGN MDO=a.b.c TYPE=HEXSTRING FROM VARS=HEXDATA

Similarly, when assigning data from an MDO into NCL variables, the data type of the output can be nominated for the MDO assignment, for example:

&ASSIGN VARS=ABC FROM MDO=a.b.c TYPE=BITSTRING

Valid type operands are:

• BOOLEAN or BOOL
• INTEGER or INT
• BITSTRING or BIT
• OCTETSTRING or OCTET
• NULL
• OBJECTIDENTIFIER or OBJECTID or OID
• OBJECTDESCRIPTOR or OBJECTDESC or ODESC
• REAL
• HEXSTRING or HEX
• NUMERICSTRING or NUMERICSTR or NUMSTR
• PRINTABLESTRING or PRINTABLESTR or PRTSTR
• IA5STRING or IA5STR
• UTCTIME or UTC
• GENERALIZEDTIME or GTIME
• GRAPHICSTRING or GRAPHICSTR or GRAPHSTR
• VISIBLESTRING or VISIBLESTR or VISSTR
• GENERALSTRING or GENERALSTR or GSTR

Type conversion is attempted regardless of the source and target types. Thus, depending on the actual value of the source data and target type, some assignments might produce valid results, while others will produce a type check.

The ASN.1 types can be classified into 3 groups:

• Graphic-oriented types:
• OBJECT IDENTIFIER, OBJECT DESCRIPTOR, UTCTime, GeneralizedTime, NumericString, PrintableString, TelexString, VideotexString, IA5String,GraphicString, VisibleString and GeneralString.
• Numeric-oriented types:
• BOOLEAN, INTEGER, BIT STRING, REAL and ENUMERATED.
• Transparent types:
• OCTET STRING, HEX STRING, SEQUENCE (OF), SET (OF), and ANY.

The following table shows the general rule for type conversion. It lists the formats of the source data value used for assignment into the target type.

For more information about the acceptable external and local form values for each type, see the Network Control Language Reference Guide.