the-failwith-function.md

title	description	ms.date
Exceptions: The failwith Function	Learn how the 'failwith' function generates an F# exception.	05/16/2016

Exceptions: The failwith Function

The failwith function generates an F# exception.

Syntax

failwith error-message-string

Remarks

The error-message-string in the previous syntax is a literal string or a value of type string. It becomes the Message property of the exception.

The exception that is generated by failwith is a System.Exception exception, which is a reference that has the name Failure in F# code. The following code illustrates the use of failwith to throw an exception.

[!code-fsharpMain]

See also

• Exception Handling
• Exception Types
• Exceptions: The try...with Expression
• Exceptions: The try...finally Expression
• Exceptions: the raise Function