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Comment by throwaway4good | Hacker News Reader

It creates the situation where these two functions appear to be identical but they are not:

   A = x * y + x

   A = y * x + x

It is an interesting subject, and in general you would want to balance usability, people's expectations, and succinctness.

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It is not the same.

   A1 = x * y + x    
   A2 = y * x + x    
   A1(1, 2), A2(1, 2)

returns results 3, 4 If You want to change parameter order, You can use Grace~ operator like this:

   A1 = x~ * y + x

it moves parameter x one position towards the end of the parameters list.

Sorry, I do not know how to post code snippets in HN properly.

Indent with 3 spaces or more.

(Two, actually.)

I think they meant:

    A1 = x * y + x
    A2 = y * x + y

A1 in Javascript pseudocode would be:

  function A1(x, y) {return x*y + x; }

But A2 would be:

  function A2(y, x) {return y*x + y; }

If you do not like the default order of implicit parameters, you can always use Grace~ operator to move x or y. Prefix form moves the parameter one position towards the beginning of the parameters list, postfix form moves one position towards the end of the parameters list:

  A1 = y~ * x + y

  A1 = y * ~x + y

or [Edit]

  A1 = y * x + y~

In the last example take into consideration, that without Grace~ operator y is the first parameter, so, you need to move it one position towards the end of the parameters list - therefore use postfix form of Grace~ operator.

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