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"Rule" (Compiled Type)

"Rule"::[tykey,tyvalue]

represents a type with specified types for key and value.

Details

  • "Rule" can be used in Typed and related constructs to specify a type.
  • "Rule" objects are automatically memory managed.
  • The key and value of a "Rule" can have any compiled type.

Constructors

  • Rules can be created with Rule (->, ) in compiled code.

Properties

  • First[rule] returns the first element of a rule.
  • Last[rule] returns the last element of a rule.
  • Information[rule,"KeyType"] for rule of type "Rule"::[tykey,tyvalue] gives tykey.
  • Information[rule,"ValueType"] for rule of type "Rule"::[tykey,tyvalue] gives tyvalue.

Conversions

    From Expressions

  • Rule expressions can be converted into compiled code elements with the type "Rule"::[tykey,tyvalue] if the first element can be converted into the type tykey and the last element can be converted into the type tyvalue.

    • To Expressions

  • "Rule" compiled elements can be converted into Rule expressions.

Examples

Basic Examples  (1)

An instance of "Rule" can be created in and returned from compiled code:

Call the function with integer and string arguments and return a rule:

Enter a rule expression and return the first element:

Enter a rule expression and return the last element: