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Well, compare Python's:

for i in range(10):

...with Go's:

for i:=0; i<10; i++ { }

An experienced programmer might have an opinion about these syntaxes but he can certainly handle both effortlessly. However, when I first saw for loops using syntax similar to Go's, I could not, for a long while, remember exactly what I have to type, and of course the compiler errors along the lines of "expecting some gibberish after some other gibberish" didn't help at all - and not knowing that they aren't supposed to help hurt, because I stared at them, trying to decipher them, instead of guessing that I got it wrong and looking up the loop syntax.

Now if you think about it, Python's incantation is very close to English ("for i in range 10" instead of "for every in the range of numbers up to 10" - you omit some words and you add 3 punctuation characters but it's close.) Go's incantation, if you try to read it, makes little sense ("for i assigned to equal 0; i less than 10; i plus plus [or i equals i plus 1]".) You mention i 3 times which is weird, because beginners actually intuitively expect DRY code (hence Java's AssWiper bill = new AssWiper [and I'm quoting from a toilet door in a CS lab] felt very weird to me for a long while.) You have those semicolons in the middle, and you're supposed to remember the order of these 3 parts - init, compare, increment.

I mean, it wasn't a huge trauma but I felt dumb for quite some hours until I got it.

(Note that i:=0 and then a while loop incrementing i are not nearly as arbitrary because you compose it out of sensible primitives. A Cish for loop on the other hand feels like one big blob of syntax which came out of nowhere. Of course once you memorize it, it's vastly more readable than a while loop because you pattern-match it and you translate it to "for every i from 0 to 10", and you assume that nobody fiddles with i midway through the loop; whereas if you see a while loop, you need to scan all of it because you will suspect that i is being fiddled with in some non-trivial way.)

Also - omitting some parts of the for loop results in syntax which is fairly crazy actually, if you read it out loud. Like for ; i<10; i++ - what's a semicolon doing after the word for?!

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// iterate half the stack: for i := 0; i < len(slice) / 2; i++ {} // iterate with a stepping: for i := 0; i < len(slice); i+=2 {} // iterate from a different starting position: for i := 5; i < len(slice); i++ {} // reverse iteration: for i := len(slice)-1; i>=0; i-- {}

1. for x := range y {...}, value iteration 2. for init; cond; post {...}, the traditional 3-element for loop 3. for cond {...}, which is basically the while loop 4. for {...}, "loop forever"

func it(n int) []struct{} { return make([]struct{}, n) } // ex. 1: for range it(10) { fmt.Println(".") } // ex. 2: for i := range it(10) { fmt.Println(i) }