# Where are control flow labels fully documented?
**URL:** https://discourse.julialang.org/t/where-are-control-flow-labels-fully-documented/137252
**Category:** General Usage
**Tags:** question, syntax, control-flow
**Created:** [May 23, 2026, 7:13am UTC](https://discourse.julialang.org/t/where-are-control-flow-labels-fully-documented/137252 "2026-05-23T07:13:20Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)
#### Post date: [May 23, 2026, 7:13am UTC](https://discourse.julialang.org/t/where-are-control-flow-labels-fully-documented/137252/1 "2026-05-23T07:13:20Z")
The documentation of `@label` is rather sparse. I am looking for a comprehensive list of
1. which forms _can be preceded_ by `@label my_label` (apparently `begin`, `for`, what else?)
2. which forms _accept_ labels (eg `break` and `@goto`, what else?)
---
### Author:  [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)
#### Post date: [May 23, 2026, 7:23am UTC](https://discourse.julialang.org/t/where-are-control-flow-labels-fully-documented/137252/2 "2026-05-23T07:23:19Z")
Ah, silly me, the feature is not even in 1.13, `master` documents is properly.
>
>
> This is a redo of #60367 taking into account various feedback on that PR. In par…ticular, it seemed like people strongly disliked the \`break break\` syntax for two primary reasons:
>
> 1. It scales poorly to multiple loops \`break break break break\`
> 2. It introduced footguns if extra loops are introduced between the loop and the break.
>
> Instead, the consensus seemed to be that labeled break should be the only facility available. Thus, this implements a proper labeled break facility that looks as follows:
>
> \`\`\`
> @label :name for i = 1:10
> for j = 1:10
> break :name (i, j)
> end
> end # evaluate to \`(1,1)
> \`\`\`
>
> The idea is to re-use the \`@label\` macro for now, but possibly promote this to syntax in a future version if it gains widespread use. Note that parser changes are still required, since the \`break\` syntax is currently an error. However, compat.jl could provide \`@goto break name val\`, which parses fine.
>
> \`continue\` is extended with label support as well:
> \`\`\`
> @label :outer while true
> for i = 1:10
> a\[i\] && continue :outer
> end
> \[...\]
> end
> \`\`\`
>
> However, the feature is not restricted to loops. A particular use case is to replace cleanup blocks written like
>
> \`\`\`
> cond1 && @goto error
> cond2 && @goto error
>
> return true
>
> @label error
> error("foo")
> \`\`\`
>
> by a labeled begin/end block:
> \`\`\`
> @label :error begin
> cond1 && break :error
> cond2 && break :error
> return true
> end
> error("foo")
> \`\`\`
>
> This doesn't save much typing work, but it makes this kind of pattern much more structured, e.g. for code-folding in IDEs.
>
> A similar pattern replaces the \`for-then\` construction originally proposed:
>
> \`\`\`
> result = @label :result begin
> for x in arr
> pred(x) && break :result x
> end
> default
> end
> \`\`\`
>
> For convenience, the label may be ommitted, in which case it defaults to \`\_\`, i.e. the above can be written as:
>
> \`\`\`
> result = @label begin
> for x in arr
> pred(x) && break \_ x
> end
> default
> end
> \`\`\`
>
> I've taken the liberty of converting some base code for testing and to give an idea of what the syntax looks like in practice, but didn't go through particularly comprehensively. These changes should be considered extended usage examples.
>
> Largely written by Claude, and I haven't looked at the implementation particularly carefully yet - for now I'm just interested in discussion of the syntax.
Sorry for the noise, I was working in nightly and reading the 1.12 docs 🤦♂️