Defining my own operator's precedence

Hi,

I have develop my own data type and my own operators on this data type. I 
could not find how to tell PostgreSQL which precedence I want to assign to 
my operator. For example, I want my unary operator "~" to have a higher 
precedence than my "+" operator. For now I have to use parenthesis to avoid 
ambiguity. I would prefer being able to define implicit precedence.

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