# (withdrawn but cannot figure out how to delete my own post)
**URL:** https://discourse.julialang.org/t/withdrawn-but-cannot-figure-out-how-to-delete-my-own-post/11048
**Category:** General Usage
**Tags:** question
**Created:** [May 21, 2018, 3:37pm UTC](https://discourse.julialang.org/t/withdrawn-but-cannot-figure-out-how-to-delete-my-own-post/11048 "2018-05-21T15:37:09Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@ronubi](https://discourse.julialang.org/u/ronubi)
#### Post date: [May 21, 2018, 3:37pm UTC](https://discourse.julialang.org/t/withdrawn-but-cannot-figure-out-how-to-delete-my-own-post/11048/1 "2018-05-21T15:37:09Z")
nevermind - problem was trailing comma on `for` statement
---
### Author:  [@kristoffer.carlsson](https://discourse.julialang.org/u/kristoffer.carlsson)
#### Post date: [May 21, 2018, 4:02pm UTC](https://discourse.julialang.org/t/withdrawn-but-cannot-figure-out-how-to-delete-my-own-post/11048/2 "2018-05-21T16:02:21Z")
Writing from my mobile so can’t check but you have a comma after the loop range in the first example.
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### Author:  [@ronubi](https://discourse.julialang.org/u/ronubi)
#### Post date: [May 21, 2018, 4:05pm UTC](https://discourse.julialang.org/t/withdrawn-but-cannot-figure-out-how-to-delete-my-own-post/11048/3 "2018-05-21T16:05:36Z")
Thanks. I figured this out while you were answering. Is there some way I can delete my own topic? (embarrassing)
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### Author:  [@kristoffer.carlsson](https://discourse.julialang.org/u/kristoffer.carlsson)
#### Post date: [May 21, 2018, 4:06pm UTC](https://discourse.julialang.org/t/withdrawn-but-cannot-figure-out-how-to-delete-my-own-post/11048/4 "2018-05-21T16:06:28Z")
No, you will forever live with the shame of having once made a typo in your code. 😉
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### Author:  [@mbauman](https://discourse.julialang.org/u/mbauman)
#### Post date: [May 21, 2018, 5:18pm UTC](https://discourse.julialang.org/t/withdrawn-but-cannot-figure-out-how-to-delete-my-own-post/11048/5 "2018-05-21T17:18:26Z")
This is actually a fairly common roadblock — one of the best reasons not to delete it is that you’re adding more search fodder for the next time someone else hits it:
>
>
>
> The following would be great to capture in some kind of error
>
> \`\`\` jl
> julia\> r =… ones(1,1)
> 1x1 Array{Float64,2}:
> 1.0
>
> julia\> for r(i) = b(prow(i))
> end
>
> julia\> r
> svec()
> \`\`\`
>
> This came up in code translated from Matlab
>
> \`\`\` jl
> for i = 1:m,
> r(i) = b(prow(i));
> end
> \`\`\`
>
> where removing the comma gives a reasonable error message. I think I've seen a similar issue with our fancy nested loop syntax before.
>
> Update: This is on 0.4. It gives an error in 0.5. Would it be possible to fix easily on 0.4?
>
>
> Discovered by Bernie Wang:
>
> The \`for\` syntax ending in a comma is invalid synta…x
> but the first code below yields the scalar 5.0 while the
> second correctly gives invalid syntax
>
> \`\`\` jl
> a = zeros(2)
> for i=1:5,
> a += \[1,1\]
> end
> a
> \`\`\`
>
> \`\`\`
> a = zeros(2)
> for i=1:5,
> a = a + \[1,1\]
> end
> a
> \`\`\`
(Note that the last two there are authored by core contributors)
---
### Author:  [@ronubi](https://discourse.julialang.org/u/ronubi)
#### Post date: [May 21, 2018, 8:58pm UTC](https://discourse.julialang.org/t/withdrawn-but-cannot-figure-out-how-to-delete-my-own-post/11048/6 "2018-05-21T20:58:28Z")
Thanks for making me feel a little better. I’m a long-time Matlab user, and many for-loop examples in that language use a trailing comma. I just did a little experiment in Matlab R2016b, and found that you can use a comma, semicolon, or just a space — even if the for-loop is all on one line, e.g.
```
>> for i=1:10 i, end
>> for i=1:10, i, end
>> for i=1:10; i, end
```
These are all syntactically okay, and execute the same way. Most of my lines of Matlab code end in semicolons to prevent the dreaded large-matrix scrolling-output problem, and I substitute commas when debugging to print intermediate values. Not sure why I got in the (bad) habit of the trailing comma on for-loops, if-blocks, etc. They might’ve been necessary in earlier versions . . .
---
### Author:  [@ronubi](https://discourse.julialang.org/u/ronubi)
#### Post date: [May 21, 2018, 9:05pm UTC](https://discourse.julialang.org/t/withdrawn-but-cannot-figure-out-how-to-delete-my-own-post/11048/7 "2018-05-21T21:05:17Z")
Interestingly, a trailing semicolon is valid in Julia:
```
julia> for i in 1:10 @show i end
julia> for i in 1:10; @show i end
```
Both lines do the same thing, whereas
```
julia> for i in 1:10, @show i end
```
produces a syntax error.