On Mon, 07 Dec 2009 16:17:10 +0300, Michal Minich
<michal.min...@gmail.com> wrote:
Hello bearophile,
Michal Minich:
But introduction "{ epx }" as delegate/function literal for functions
with no arguments, which implicitly returns result of the expression,
seems to me as a good idea.
It's a special case, and special cases help to kill languages. It's
not important enough.
But a general shorter syntax for lambdas is possible, like the C# one.
Evaluations lazy arguments only 0 or 1 times sounds like a nice idea.
Bye,
bearophile
Yes, it works well in C#, and it is one of the best extension of this
language (only adding generics was better).
Consider how it works in C#, and how it could in D
// 1. lambda with no parameter int a;
var t = new Thread ( () => a=42 );
// 2. lambda with one parameter
string[] arr;
Array.FindAll (arr, item => item.Contains ("abc"));
// 3. lambda with more parameters
Foo ( (a, b) => a + b );
// 4. lambda with statement (previous examples were expressions)
Array.FindAll (arr, item => { return item.Contains ("abc"); } );
// curly braces, semicolon and return are required when statement is
used.
D could use:
1. auto t = new Thread ( { a=42 } );
or auto t = new Thread ( () { a=42 } );
It already works, just try it (but don't forget to put a semicolon at the
end).
2. array.findAll (arr, (item) { item.contains ("abc") } );
3. foo ( (a, b) { a + b } );
4. array.findAll (arr, (item) { return item.contains ("abc"); } );
I'm not proposing this syntax (maybe I probably should, but I have
feeling I would not be first). It may not even be possible to parse it,
but seems to me more similar to how currently functions are written. In
this setting {exp} or {stm} is not *special* case.
I believe it would work. And yes, it was already proposed by many others.
