Just watched Gary Bernhardt’s “wat”. JavaScript:

It is so nice to work with a sane programming language

rather than this lunacy!

Julia isn’t exactly immune to this kind of interesting behavior. What does

```
function g(a)
if a
f() = 2
else
f() = 3
end
return f
end
```

Yes, this one is weird. It does have a “right” way solution though:

```
julia> function g(a)
if a
f = () -> 2
else
f = () -> 3
end
return f
end
g (generic function with 1 method)
julia> g(true)()
2
julia> g(false)()
3
julia>
```

The wrong way just needs to be caught by the compiler, I think.

By the way, if you know of some weirdness in Julia, do post it here please.

```
f = 2
f1 = 2
2f + 2f1
```

edit: heh, nice, discourse highlighting gives it away

```
julia> a = -1
-1
julia> 1^a === 1^(-1)
false
```

```
julia> a = 1; b = 2; a + b = 3;
julia> 1 + 4
3
```

```
julia> a = 1 + 2
- 3
-3
julia> a
3
```

Nice! Should

```
julia> x + y = 2
+ (generic function with 1 method)
```

just be forbidden?

```
julia> a = 1; b = 2; a + b = 3
ERROR: error in method definition: function Base.+ must be explicitly imported to be extended
Stacktrace:
[1] top-level scope at none:0
[2] top-level scope at REPL[10]:1
```

A bit of protection…

If you have used `Base.+`

, in the module, yes.

Haha! What a fantastic thread! For readers not so familiar with Julia, most of these are mere curiosities, I’ve never had any of them creep up on me (save perhaps thinking I was adding methods to Base functions without remembering to import them first). Julia is *highly* consistent and sane in my experience…

Numbers being iterable and trailing 1 indexes can be somewhat surprising:

```
julia> size(1.0)
()
julia> 1.0[1, 1, 1]
1.0
julia> collect(1.0)
0-dimensional Array{Float64,0}:
1.0
```

I encountered both wats above in real-world code. The worst was when had a complicated interpolation scheme where I sampled a function `f(x,y)`

at points 0, 1 and 2 in both directions, and wanted to compute a second derivative with `(f02 - 2f01 + f00)`

. That was a fun hour debugging why my results were wrong… (and not even completely wrong, since my function f was about 10…) In general though I agree with you, julia is pretty consistent.

```
julia> where where where where where where where
Any
```

This seems to be happening with any odd number of `where`

greater than 1?

It is basically

```
T where T where S
```

with the symbol `where`

instead of `T`

and `S`

.

I always thought writing `1x`

and `2f`

instead of `1*x`

and `2*f`

was a bad idea.

As my father used to say “just because you could doesn’t mean you should”.

I much prefer `2π`

over `2*π`

, which is better still than `2*pi`

or the ugliest `=2*PI()`

. Also I like being able to write `√(2log(2))`

.

But every once in a while I get carried away and try to write `2πf`

, which doesn’t work out so well.

How many times have I or my students been caught out by `for i in n`

instead of `for i in 1:n`

. I really wish the former was just made a syntax error.

Conversely, I often find this syntax convenient.