Question

How can I set priority for custom operators? (if that is possible)

like * or / has higher priority then + or - I want to add such rule to my operators.

Answer 1

Precedence is decided by the table at the bottom of this page: http://msdn.microsoft.com/en-us/library/dd233228.aspx

In particular the order is :

|,’,’,||,&,&&,< op, >op, =, |op, &op,&&& , |||, ^^^, ~~~, <<<, >>>,^ op,::,- op, +op,
(binary),* op, /op, %op,** op,prefix operators (+op, -op, %, %%, &, &&, !op, ~op)

From the same page:

F# supports custom operator overloading. This means that you can
define your own operators. In the previous table, op can be any valid
(possibly empty) sequence of operator characters, either built-in or
user-defined. Thus, you can use this table to determine what sequence
of characters to use for a custom operator to achieve the desired
level of precedence. Leading . characters are ignored when the
compiler determines precedence.