HoldAllComplete
is an attribute which specifies that all arguments to a function are not to be modified or looked at in any way in the process of evaluation.
Details
- By setting the attribute HoldAllComplete, you can effectively shield the arguments of a function from all aspects of the standard Wolfram Language evaluation process.
- HoldAllComplete not only prevents arguments from being evaluated, but also prevents Sequence objects from being flattened, Unevaluated wrappers from being stripped, and upvalues associated with arguments from being used.
- Evaluate cannot be used to override HoldAllComplete.
Examples
open all close allBasic Examples (1)
Properties & Relations (4)
HoldComplete is a standard container with attribute HoldAllComplete:
No form of evaluation control affects an expression with attribute HoldAllComplete:
Substitution still happens inside an expression with attribute HoldAllComplete:
Unevaluated has the attribute HoldAllComplete:
Possible Issues (2)
HoldAllComplete affects only evaluation; input transformations are still applied:
HoldAllComplete does not prevent formatting:
Add DisableFormatting to prevent formatting:
Neat Examples (1)
A fast way to compute the Hofstadter–Conway sequence [more info]:
Text
Wolfram Research (1996), HoldAllComplete, Wolfram Language function, https://reference.wolfram.com/language/ref/HoldAllComplete.html.
CMS
Wolfram Language. 1996. "HoldAllComplete." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/HoldAllComplete.html.
APA
Wolfram Language. (1996). HoldAllComplete. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/HoldAllComplete.html