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Comment by HALtheWise | Hacker News Reader

One really nice feature from Wolfram Mathematica that few other languages seem to have is a special prefix-only syntax for single-argument function application. In Mathematica, it's f@x ==> f(x), and it's really convenient because it prevents needing to move your cursor to the end to put in a closing paren. Since it only works for single-argument functions, there's no ambiguity.

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In any case, this can be done now with a helper class used as a decorator.

  >>> class At:
    __slots__= 'fun',
    def __init__(self, fun):
      self.fun = fun
    def __matmul__(self, arg):
      return self.fun(arg)
    def __call__(self, *args, **kwargs):
      return self.fun(*args, **kwargs)

  >>> @At
  def square(x):
    return x*x

  >>> square(2)
  4
  >>> square@2
  4

There is nothing nice about it. Not even in a REPL. Preventing a simple move of the cursor does not justify complexity and yet another way to apply a function.

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