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defining unary operators
f#

> let (<?>) a = -a;;val ( <?> ) : int -> int> <?> 1;; <?> 1;; ^^^^stdin(3,1): error FS0010: Unexpected infix operator in definition> (<?>) 1;;val it : int = -1How can I use my operator without brackets?

And second question:
> let (&) a = -a;;
let (&) a = -a;; -----^^
stdin(18,6): warning FS0086: The '&' operator should not normally be
redefined. Consider using a different operator name.
val ( & ) : int -> intI had the warning, but F# executed my code. But here:
> let (|) a = -a;;
let (|) a = -a;; ------^^
stdin(21,7): error FS0010: Unexpected symbol ')' in binding. Expected
identifier or other tokenF# printed the error. I have same error with ? operator. What do I wrong?

.

See "Operator Names"

[link:research.microsoft.com]

(especially the bit about prepending a twiddle (~) for prefix ops) and "Symbolic Operators"

[link:research.microsoft.com]

for some details, though I am not sure if the spec is sufficiently complete to answer all these questions.

By on 1/12/2009 8:01 PM ()

Unfortunately I got same error with tilda sign:
> let (~<?>) a = -a;;
val ( ~<?> ) : int -> int
> <?>1;;
<?>1;; ^^^^
stdin(23,1): error FS0010: Unexpected infix operator in definition
And symbolic names can be '?' and '|':

regexp first-op-char =

!$%&*+-./<=>?@^|~

regexp op-char = first-op-char | :

token symbolic-op =

| first-op-char op-char*

Or I don't understand the documetation. :(Anyway, thanks for your answer.

By on 1/12/2009 8:17 PM ()

> let (~<?>) a = -a;;
val ( ~<?> ) : int -> int
> <?>1;;
<?>1;; ^^^^Interesting. This code works fine:

> ~<?>1;;val it : int = -1>

By on 1/12/2009 9:55 PM ()

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