Syntax poll, take 2

[Reinier Zwitserloot]

I'm concerned that this poll relies a little too much on your average
lambda-devver experimenting.

The instructions include examples, but these examples are rather unlikely to
be representative of what Joe Java is _ever_ going to write. Anyone filling
in this poll based primarily on looking at them is going to make an
uninformed decision.

All examples in the instructions share 2 properties:

(A) They are a single expression.

(B) They are written as a physical single line. (one-liner).

While some closures will certainly be a single expression, I'd expect many
(probably over three quarters*) to be multi-statement, and some to be single
statement, which is for some proposals actually relevant. Piling multiple
statements all on one line is obviously not going to happen in actual live
code use, and the instructions do not offer any suggestion as to what that
would look like (in fact, in many cases the syntax isn't even clear!)

More to the point, writing these things in a single line does not seem like
something Joe Java will ever do. The majority of the community will refuse
to write something like:

if (x == null) return null;

instead adding braces and some newlines. Given that the community evidently
finds that too complicated to one-line, I fail to see how any of the closure
examples are palatable to Joe Java. Why do we think closures will all of a
sudden cure Joe from his obsession with line breaks?

The only one of the 4 proposals that is obviously line-breakable is strawman
(newline after the brace, just like everywhere else in java). For all other
proposals I'd like to see a style guide which is suitable for Joe Java (i.e.
does not attempt to pile too much into a single line), and which is
virtually enforced (i.e. consistently applied everywhere, with a link to a
style guide distributed at the same time as the official proposal) as lambda
is promoted to blogs and eventually java 8, so that most of the community
ends up using a single style to write them. Nothing is more annoying than a
language where the community breaks into a near even split across various
completely different styles. See tabs v. spaces debate. I doubt anyone would
argue that's good for the language.


*) Very *very* few closures used in my own code as well as open source
projects I looked at ever use closures with a tiny one-expression body.
However, if lambdas had been in java, code that currently doesn't use
closures might have used closures, i.e. the balance between one-expression
closures and (much) larger ones is different when closures are easier to
use. Nevertheless, it seems obvious that multi-statement closures will not
all of a sudden become the rare case when lambda is out.

 --Reinier Zwitserloot



On Sat, Jun 11, 2011 at 9:44 PM, Brian Goetz <brian.goetz at oracle.com> wrote:

> > I'm curious - why the 100 responses limit? Is that how few people are
> > subscribed to lambda-dev? (I can't check myself right now, sorry)
>
> Partially laziness -- the easiest way to do the survey was the free
> SurveyMonkey account, which is limited to 100.  There are ~300
> subscribers on lambda-dev, but only ~100 that have posted.  So the
> laziness-induced limit seemed adequate to the task.  And if 100 is not
> enough, 200 (two polls) will surely be.
>
> The polluted poll has been set aside and you have a chance to express
> yourself in the new one.
>
>