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Instant-use add-on functions for the Wolfram Language
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Define a data structure that can refer to its own values to compute new ones
ResourceFunction["AssociationTemplate"][assoc] creates an Association-like object in which RuleDelayed (⧴) values can be combined with TemplateSlots and Functions to create values that depend on other keys. |
Define an AssociationTemplate in which the first key acts as a parameter for a computation:
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Query a value:
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Use a two-argument query to temporarily override keys with new (non-templated) values. The second argument has to be an Association:
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Query all keys and return the result as an Association:
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Use Append or Prepend to create a new AssociationTemplate with a different key value:
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AssociationTemplate can be used with the functions Length, Keys, Values and Normal:
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Normal will turn all templated values into a TemplateExpression or TemplateObject or leave them as a Function:
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Join two templates together:
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It is possible that some keys can return different values with each query:
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Within a single query, the values will be consistent and each key will be evaluated no more than once:
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AssociationTemplate will return a Failure object if cyclical dependencies are detected:
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