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In the example of a template:
Dear .. The power consumption at the design speed is #VDES|F6.2# knots. #NS=2[1]#The vessel has two propellers[1] With best regards, #PROJMANNAME$#
In this example NS=2 is an expression that controls everything between the [1] labels. When true, the text between "[1]#" and "propellers[1]" is added, if false the part between "#NS" and "propellers[1]" is removed.
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