PreDecrement 
--x
decreases the value of x by 1, returning the new value of x.
Details
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- --x is equivalent to x=x-1.
- PreDecrement has attribute HoldFirst.
- In PreDecrement[x], x can be a symbol or other expression with an existing value. »
Examples
open allclose allScope (4)
Decrement all values in a list:
The argument to PreDecrement need not be a symbol:
Properties & Relations (4)
Decrement and PreDecrement differ in the return value of the operation:
PreDecrement is a short form of this assignment:
PreDecrement is a special case of SubtractFrom:
Increment and PreIncrement are closely related operations:
Text
Wolfram Research (1988), PreDecrement, Wolfram Language function, https://reference.wolfram.com/language/ref/PreDecrement.html.
CMS
Wolfram Language. 1988. "PreDecrement." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/PreDecrement.html.
APA
Wolfram Language. (1988). PreDecrement. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/PreDecrement.html