shing something onto a stack, or processing some of the tokens on the tops of the stacks.</P>
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If an error occurs, the parser may take two different actions. Some errors are pushed on the argument stack; these may be handled by functions. For example, if the result of an expression is too large to be represented, the evaluator will just push PSEE_FLOAT_POS_INFINITY on the argument stack. Any function or operator which is passed an error code as an argument can either handle the error, propagate the error