Re: Coroutines and Go

[David Given <dg@...>]

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Mark Hamburg wrote:
[...]
> On the other hand, it's probably better formatted as:
> 
> 	func( p* ByteSlice ) Write( data[] byte )( n int, err os.Error )

Go's * type modifier binds to the type, not the variable name, so:

    var i, j *int;

...actually defines two pointers.

[...]
> I'm still finding Write to feel lost in that notation, however.

Algol-68 doesn't have methods or return parameters, so the above would
probably have to be written using pass-by-reference paramteres as:

  PROC Write = (REF []BYTE p, []BYTE data, REF INT n, REF OSError err):
  BEGIN
      ~
  END

Putting the [] before the type looks weird to my C-trained eyes, but I
quite like the way the 'Write' is brought out to be the first
non-keyword on the line. I also like Algol-68's implicit slice
functionality --- Go's explicit differentiation between arrays and
slices seems like a big step backwards, IMO.

(In fact, a more Algol-68ish way of representing the append operation
would be:

  PROC append = (REF FLEX []BYTE buffer, []BYTE data) VOID:
    FOR i FROM LWB data TO UPB data DO
      buffer[UPB buffer + 1] := data[i]
    OD;

FLEX arrays automatically resize themselves... and does that inside of
the loop look familiar? Particularly if you realise that you can rewrite
it as:

      buffer[⌈buffer + 1] := data[i]

Lua, of course, doesn't have explicit typing, but one obvious syntax
extension for types would be:

  function append(buffer: ByteArray, data: const ByteArray): void

But that's simply because it's convenient to put an optional : after
each parameter.

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