David Bolen wrote:
I think this specific use case -- defining callbacks -- should be
addressed, rather than proposing a solution to something that isn't
necessary. (...)
I'd be interested in this approach too, especially if it made it simpler
to handle simple manipulation of callback arguments (e.g., since I often
ignore a successful prior result in a callback in order to just move on
to the next function in sequence).
It seems to me that what most people *actually* want, when asking for lambdas, is a quicker and more convenient way to get closures. (At least, that's what the vast majority of examples of lambda use seem to be for.) Perhaps one could get a bit more traction by looking for improved closure syntax instead of focusing on the anonymous function aspect.
All of the suggestions for anonymous multiline functions (with embedded indentation) seem to me to miss what seems to me to be the only significant benefit of lambda -- its ability to be used in-line without creating a huge ugly tangle. (I'd argue that lambdas create a *small* ugly tangle, but apparently that's just me. ;) ) Lambdas do have some value in defining callbacks, but that value derives almost exclusively from the fact that they are in-line (rather than a few lines above). Mimicking function-def indentation inside of another function's arglist strikes me as an abomination just waiting to happen; in comparison, the need to type a name twice seems trivial.
As a result, it seems to me that, rather than generalize lambdas into "full" anonymous functions (with most of the negatives and few of the positives of lambda), it would be much better to specialize them further into inline-closure-creators, where they can serve a valuable purpose without quite as much risk of code pollution.
Jeff Shannon Technician/Programmer Credit International
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