"Ian Bicking" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED]
John Roth wrote:The syntax I prefer (and I don't know if it's actually been suggested before) is to use braces, that is { and }.
In other words, an anonymous function looks like: {p1, p2, p3 | stmt1 stmt2 }
What's the advantage of something like that over the non-anonymous equivalent:
def some_func(p1, p2, p3): stmt1 stmt2
I appreciate some of the motivation, but merely avoiding giving something a name doesn't seem like a laudible goal.
Actually, it is a laudable goal. It's always easier to understand something when it's right in front of your face than if it's off somewhere else.
This, of course, trades off with two other forces: avoiding repetition and making the whole thing small enough to understand.
So the niche is small, single use functions. The problem with lambdas is that they're restricted to one expression, which is too small.
Languages that are designed with anonymous functions in mind use them very heavily. Smalltalk is the standard example, and it's also one of the major (possibly the only) attraction Ruby has over Python.
Python isn't designed that way, which restricts their utility to a much smaller niche than otherwise.
The one motivation I can see for function expressions is callback-oriented programming ...
Well, that's true, but that's a very global statement: when you pass a function into another routine, it's essentially a callback.
...
Function expressions could get really out of hand, IMHO, and could easily lead to twenty-line "expressions". That's aesthetically incompatible with Python source, IMHO.
Anything can get out of hand; there's no way of legislating good style without restricting the language so much that it becomes unusable for anything really interesting. Even then it doesn't work: see COBOL as a really good example of good intentions gone seriously wrong.
Have you ever programmed in a language that does use anonymous functions extensively like Smalltalk?
John Roth
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Ian Bicking / [EMAIL PROTECTED] / http://blog.ianbicking.org
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