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A.3.2 Function Arguments
The main expression or object on which a built-in function acts is usually given as the first argument to the function. Subsidiary parameters appear as subsequent arguments.
The following are exceptions:
In functions like Map and Apply, the function to apply comes before the expression it is to be applied to.
In scoping constructs such as Module and Function, local variables and parameter names come before bodies.
In functions like Write and Display, the name of the file is given before the objects to be written to it.
For mathematical functions, arguments that are written as subscripts in standard mathematical notation are given before those that are written as superscripts.