Teledyne LeCroy Merlins Wand - Users Manual - Manual (Page 273)

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CATC M ERLIN ’ S W AND 2.00 C HAPTER D
User’s Manual CATC Scripting Language
Lists
A list can hold zero or more pieces of data. A list that contains zero pieces
of data is called an empty list. An empty list evaluates to false when used in
an expression, whereas a non-empty list evaluates to true. List literals are
expressed using the square bracket ([]) delimiters. List elements can be of
any type, including lists.
[1, 2, 3, 4]
[]
["one", 2, "three", [4, [5, [6]]]]
Raw Bytes
Raw binary values are used primarily for efficient access to packet
payloads. A literal notation is supported using single quotes:
'00112233445566778899AABBCCDDEEFF'
This represents an array of 16 bytes with values starting at 00 and ranging
up to 0xFF. The values can only be hexadecimal digits. Each digit
represents a nybble (four bits), and if there are not an even number of
nybbles specified, an implicit zero is added to the first byte. For example:
'FFF'
is interpreted as
'0FFF'
Null
Null indicates an absence of valid data. The keyword null represents a
literal null value and evaluates to false when used in expressions.
result = null;
D.3 Variables
Variables are used to store information, or data, that can be modified. A
variable can be thought of as a container that holds a value.
All variables have names. Variable names must contain only alphanumeric
characters and the underscore ( _ ) character, and they cannot begin with a
number. Some possible variable names are
x
_NewValue
name_2