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prefix

If the Record Node has a child Name Node, setting this attribute will apply the value of the attribute, followed by an underscore, as a prefix to the name read from the file into the Name Node.

This can be useful if the value read can start with a number, or other value which would be invalid when used in a PhixFlow Attribute Expression.

Any string

No

None

discriminator

If a record has a child Tag Node, then this string will be used as the discriminator for the Tag Node, unless a discriminator is also set on the Tag Node itself, which will override it.

See Attribute Node for details of the discriminator attribute.

Any:

• string, or
• hex string, e.g A0FF08, if the hexDiscriminator attribute is set to T.

No

None

hexDiscriminator

Whether the discriminator will be given as a hex string.

If the discriminator cannot be specified as an ASCII string then it can be specified as a hex string, where each pair of characters in the string represent a hex digit.

T for true or F for false

No

F

length

This overall length, as number of bytes, expected for all Attribute Nodes within the hierarchy of the Record Node.

This is helpful if the fields that make up the record in the file include optional fields – setting the length helps the grammar to determine where the record ends.

Any of:

• a number (the number of bytes)
• a variable name, the variable holding the number of bytes – this variable must have been declared in the variables attribute of this or an ancestor node
• an Expression inside curly braces which will calculate a whole number. The Expression may refer to Attribute Nodes which have been declared in the scriptVariables attribute of this or an ancestor node.

No

None