is a name for a message.


  • You can specify messages by defining values for symbol::tag.
  • symbol::tag is converted to MessageName[symbol,"tag"]. tag can contain any characters that can appear in symbol names. symbol::"tag" can also be used.
  • Assignments for s::tag are stored in the Messages value of the symbol s.
  • The f::usage message is typically defined for functions intended for general use, giving a description of how to use the function.
  • ?f prints out the message f::usage.
  • When ?form finds more than one function, only the names of the functions are printed.
  • You can switch on and off messages using On[s::tag] and Off[s::tag].
  • MessageName[symbol,"tag","lang"] or symbol::tag::lang represents a message in a particular language.


open allclose all

Basic Examples  (2)

Define a usage message for a function:

Show the usage message:

Process messages generated during an evaluation:

Scope  (1)

Define a function that will test another function and give the argx message if needed:

Define g to use the test and return unevaluated when it fails:

Wolfram Research (1988), MessageName, Wolfram Language function, (updated 2002).


Wolfram Research (1988), MessageName, Wolfram Language function, (updated 2002).


Wolfram Language. 1988. "MessageName." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2002.


Wolfram Language. (1988). MessageName. Wolfram Language & System Documentation Center. Retrieved from


@misc{reference.wolfram_2024_messagename, author="Wolfram Research", title="{MessageName}", year="2002", howpublished="\url{}", note=[Accessed: 21-July-2024 ]}


@online{reference.wolfram_2024_messagename, organization={Wolfram Research}, title={MessageName}, year={2002}, url={}, note=[Accessed: 21-July-2024 ]}