VariableList

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A VariableList is a link type used to declare a list of variables. It can be used to define a signature for a LambdaLink or a BindLink. A variable list consists entirely of a set of variable and variable type declarations, and nothing more.

For example:

VariableList
   VariableNode "$A"
   VariableNode "$B"

declares an argument list consisting of two arguments. A more complex example, consisting of type declarations for the variables, would be:

  VariableList
      TypedVariableLink
         VariableNode $F
         TypeNode "ConceptNode"
      TypedVariableLink
         VariableNode $C
         TypeNode "ConceptNode"

declares a signature where both arguments must be ConceptNodes.