Juniper JUNOSE 11.3, Руководство по настройке

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Table 53: Operator Actions (continued)
Action Operator Operation
Increments the variable before the expression is
evaluated ++ Preincrement
Decrements the variable before the expression is
evaluated – – Predecrement
Reverses the logical state of its operand. 0 is returned
for nonzero operands. 1 is returned for operands that
evaluate to zero. ! Negation
Provides the absolute value of the value + Arithmetic (unary)
Provides the inverse of the value – Arithmetic (unary)
Extracts a portion of a string substr() Substring
Generates a random integer between the provided
endpoints, inclusive rand() Randomize
Rounds the value to the nearest integer round() Round
Truncates a noninteger value to the value left of the
decimal point truncate() Truncate
Assignment
Use the assignment operator (:=) to set the value of a local variable. The expression to
the right of the operator is evaluated, and then the result is assigned to the local variable
to the left of the operator. The expression to the right of the operator can include the
local variable if you want to modify its current value.
Example
<# i := i + 1 #>
<# count := count - 2 #>
Increment and Decrement
You can use the increment operator (++) to increase the value of a local variable by one.
You specify when the value is incremented by the placement of the operator. Incrementing
occurs after the expression is evaluated if you place the operator to the right of the
operand. Incrementing occurs before the expression is evaluated if you place the operator
to the left of the operand.
Example 1
<# i := 0; j := 10 #>
<# j := j - i++ #>
In Example 1, the result is that i equals 1 and j equals 10, because the expression is
evaluated (10 – 0 = 10) before i is incremented.
Example 2
<# i := 0; j := 10 #>
<# j := j - ++i #>
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JunosE 11.3.x System Basics Configuration Guide