HoldAll

HoldAll

is an attribute that specifies that all arguments to a function are to be maintained in an unevaluated form.

Details

  • You can use Evaluate to evaluate the arguments of a HoldAll function in a controlled way.
  • Even when a function has attribute HoldAll, Sequence objects that appear in its arguments are still by default flattened, Unevaluated wrappers are stripped, and upvalues associated with the arguments are used.

Examples

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Basic Examples  (1)

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Applications  (3)

Properties & Relations  (14)

See Also

Unevaluated  Hold  HoldFirst  HoldRest  NHoldAll  HoldAllComplete  SequenceHold  Inactivate  Extract

Tutorials

Introduced in 1988
(1.0)