On: Google Go: Good For What?

[tptacek]

From a previous Go blog post by the same author:

Go decided to use a foreign syntax to C++, C and Java programmers. They borrows forward declarations from BASIC (yep, you heard me right…BASIC), creating declarations that are backwards from what we’ve been using for close to 20 years

"Yep, you heard me right... BASIC". Consider carefully how seriously you want to take this blog.

[mseepgood → tptacek]

Go's declaration syntax has some benefits: http://blog.golang.org/2010/07/gos-declaration-syntax.html

And they didn't borrow the declaration syntax from BASIC, but from Pascal: http://golang.org/doc/go_faq.html#ancestors

At the time Pascal was invented BASIC distinguished variable types via name postfixes like % and $.

Also, a "forward declaration" is not what the author seems to think: http://en.wikipedia.org/wiki/Forward_declaration

[snogglethorpe → mseepgood]

What really annoys me about Go's declaration syntax is that they left out the colon.

Like Pascal/Ada/etc, Go uses a postfix type declaration syntax, but the former languages separate the variable from the type with a colon. This is both more readable—the colon acts as a highly visible marker for the type, whereas with the Go style, the variable and type end up sort of smudged together—and because of its long history, much more familiar.

Go-style: var foo, bar int

Pascal-style: var foo, bar : int

My suspicion is that Go originally did use a colon in declarations and they got rid of it at some point for some reason, because Go's "auto-declaration" syntax actually does use a colon, only without an explicit type: "x := expr" makes much more sense if the normal declaration syntax is "x : type = expr" ("just leave out the type and it will be deduced")....

There doesn't seem any particularly good reason to omit the colon, it's neither onerous to use nor particularly space-consuming. Neither is it likely it simply didn't occur to them, as the declaration syntax is probably consciously based on that of Pascal-family languages. Given that it seem to yield obvious benefits without any obvious problems, I'm mystified as to why it was omitted.

Unfortunately for all its obvious goodness in some areas Go also seems to have a number of these "WTF were they thinking" areas as well. The impression it leaves is of a rough draft, not something polished. Sadly, these quirks are pretty much set in stone now...

[wtetzner → tptacek]

I haven't written any Go, but the FAQ (http://golang.org/doc/go_faq.html#principles) says:

"There are no forward declarations and no header files; everything is declared exactly once."

Is the author just wrong, or has the language changed since the FAQ was last updated?

[mseepgood → wtetzner]

He confuses forward declarations with "declaring the type before the variable name".

[nollidge → mseepgood]

I think you mean "declaring the variable name before the type".

So C is "int x" where Go is "x int". BASIC is typically more like "DIM x AS INTEGER".

[tptacek → nollidge]

For the record: as someone who started in the early '90s in C, I hate hate hate the Go declaration syntax. But the designers make a very compelling case for why it's the right syntax: C function pointers are needlessly convoluted.

[erichocean → tptacek]

Scala is the same way, and their rational is that it makes it easy (in the parser, I guess) to just omit the type.

It is weird at first, but you get used to it, like everything syntactic.

[batista → tptacek]

>For the record: as someone who started in the early '90s in C, I hate hate hate the Go declaration syntax.

Why hate something trivial that takes 2 minutes to adjust to and has benefits without any drawbacks whatsoever?

[thebigshane → batista]

Doesn't hating something usually imply that one is being irrational about it?

I'm sure `tptacek` will get over it :-)