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The fixity of (binary) operators operators can be specified using the following syntax.
There are three kinds of fixity, non-, left- and right-associativity (
infix n op infixl n op infixr n op
Here n is a number [0..] indicating the operator's precedence and op an operator (simply a function), for example of the form
_*_. A higher number means the precedence is higher, i.e. the operator binds more strongly than an operator with a lower numeric value.
If you don't know much about associativity or fixity, See wikipedia.