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2.1 A few comments on syntax

First of all, there are two types of parameters in a simulation file: compulsory and optional parameters. Optional parameters are always specified within a braced block (i.e. a block of text delimited by braces ({ like this }). They also often take the form

parameter = value
where parameter is an unique identifier (within this braced block). All the other parameters are compulsory parameters. For example, in vorticity.sim both
  GfsTime { end = 0 }
and
end = 0
are optional parameters.

The second important syntax point regards the way various fields are delimited. Newline (or ``carriage return'') characters are generally used to delimitate different ``objects'' in the simulation file. The only case where this rule does not apply is within braced blocks defining optional arguments of the form

parameter = value
For example, in vorticity.sim the following blocks of text are all objects: Following this rule, vorticty.sim could have been written equivalently as:
1 2 GfsSimulation GfsBox GfsGEdge {} { GfsTime {
  end = 0 }
}
GfsBox {}
1 1 right
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