# Internals & Design

**URL:** https://discourse.julialang.org/c/dev/5.md?page=41

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**Page:** 42

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## [\[Feature\] why not a \`functionswith\` method?](https://discourse.julialang.org/t/feature-why-not-a-functionswith-method/35409)

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**Author:** [@Iagoba\_Apellaniz](https://discourse.julialang.org/u/Iagoba_Apellaniz)\
**Replies:** 6\
**Last updated:** [March 2, 2020, 4:11pm UTC](https://discourse.julialang.org/t/feature-why-not-a-functionswith-method/35409 "2020-03-02T16:11:12Z")

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The idea is to print a simpler and shorter list than methodswith. Since we have methodswith and methods, and the function name of a method is obtained by accessing it name field, for me it seems that functionswith is mis…

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## [Handy function for making empty arrays](https://discourse.julialang.org/t/handy-function-for-making-empty-arrays/35241)

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**Author:** [@Tbl](https://discourse.julialang.org/u/Tbl)\
**Replies:** 5\
**Last updated:** [February 29, 2020, 3:19pm UTC](https://discourse.julialang.org/t/handy-function-for-making-empty-arrays/35241 "2020-02-29T15:19:24Z")

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I am teaching Julia to students with Python background and one thing cough my attention: there are few useful functions for making basic matrices, like zeros, ones, trues, falses, fill, similar, but there is no such func…

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## [Dates: picosecond, femtosecond, attosecond period](https://discourse.julialang.org/t/dates-picosecond-femtosecond-attosecond-period/35066)

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**Author:** [@larschrj](https://discourse.julialang.org/u/larschrj)\
**Replies:** 2\
**Last updated:** [February 24, 2020, 10:39am UTC](https://discourse.julialang.org/t/dates-picosecond-femtosecond-attosecond-period/35066 "2020-02-24T10:39:08Z")

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Is there any argument against adding picosecond, femtosecond, attosecond periods to Dates? (e.g. performance or bloating stdlib code) Otherwise I’d like to do so.

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## [Pkg new telemetry options](https://discourse.julialang.org/t/pkg-new-telemetry-options/35023)

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**Author:** [@longemen3000](https://discourse.julialang.org/u/longemen3000)\
**Replies:** 0\
**Last updated:** [February 22, 2020, 5:44pm UTC](https://discourse.julialang.org/t/pkg-new-telemetry-options/35023 "2020-02-22T17:44:57Z")

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This is mainly a placeholder to put information on the new pkg telemetry protocol

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## [Broadcasting over an anonymous function much slower than map](https://discourse.julialang.org/t/broadcasting-over-an-anonymous-function-much-slower-than-map/34874)

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**Author:** [@bkamins](https://discourse.julialang.org/u/bkamins)\
**Replies:** 4\
**Last updated:** [February 21, 2020, 5:35pm UTC](https://discourse.julialang.org/t/broadcasting-over-an-anonymous-function-much-slower-than-map/34874 "2020-02-21T17:35:56Z")

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I am on Julia 1.3. I do not understand why broadcasting over an anonymous function is much slower than map: julia\> x1, x2 = rand(10^6), rand(10^6); julia\> @time ((x1, x2) -\> x1 \< x2).(x1, x2); 0.265166 seconds (241.2…

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## [Executing on the root Task from the REPL](https://discourse.julialang.org/t/executing-on-the-root-task-from-the-repl/34801)

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**Author:** [@mkitti](https://discourse.julialang.org/u/mkitti)\
**Replies:** 0\
**Last updated:** [February 18, 2020, 10:39am UTC](https://discourse.julialang.org/t/executing-on-the-root-task-from-the-repl/34801 "2020-02-18T10:39:11Z")

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I would like to a explore a mechanism by which a user could execute a command from the REPL on the root task rather than the backend. Motivation: JavaCall Without JULIA\_COPY\_STACKS=yes it appears JavaCall will only fun…

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## [Broadcast vs. scalar loop, can Julia vectorize better?](https://discourse.julialang.org/t/broadcast-vs-scalar-loop-can-julia-vectorize-better/34617)

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**Author:** [@HenrikM](https://discourse.julialang.org/u/HenrikM)\
**Replies:** 8\
**Last updated:** [February 15, 2020, 7:28pm UTC](https://discourse.julialang.org/t/broadcast-vs-scalar-loop-can-julia-vectorize-better/34617 "2020-02-15T19:28:54Z")

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Or is there something wrong with my code? Below is a MVE of my code. func1 and func2 do the same thing. Why is func2 faster than func1? Why can’t the compiler figure it out? I think func1 more clearly expresses my inte…

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## [Julia relative imports, issue #4600, exactly how "not that difficult" is it?](https://discourse.julialang.org/t/julia-relative-imports-issue-4600-exactly-how-not-that-difficult-is-it/34503)

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**Author:** [@DevJac](https://discourse.julialang.org/u/DevJac)\
**Replies:** 5\
**Last updated:** [February 14, 2020, 6:21pm UTC](https://discourse.julialang.org/t/julia-relative-imports-issue-4600-exactly-how-not-that-difficult-is-it/34503 "2020-02-14T18:21:18Z")

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I’ve reached the point in my Julia journey where I’m seeing the limitations of include for assembling lots of modules into a project. It seems https://github.com/JuliaLang/julia/issues/4600 is the answer, but progress se…

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## [Add composition operator ⨟ Unicode 2A1F for flipped ∘](https://discourse.julialang.org/t/add-composition-operator-unicode-2a1f-for-flipped/34436)

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**Author:** [@schlichtanders](https://discourse.julialang.org/u/schlichtanders)\
**Replies:** 10\
**Last updated:** [February 11, 2020, 8:16am UTC](https://discourse.julialang.org/t/add-composition-operator-unicode-2a1f-for-flipped/34436 "2020-02-11T08:16:08Z")

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Dear Julia designers, having read parts of the Applied Category Book Seven Sketches of Compositionality by Brendan Fong and David I. Spivak I really appreciate the use of the \\fatsemi operator ⨟ It is just the reversed…

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## [When does Code get optimized for architecture](https://discourse.julialang.org/t/when-does-code-get-optimized-for-architecture/34213)

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**Author:** [@Crown421](https://discourse.julialang.org/u/Crown421)\
**Replies:** 7\
**Last updated:** [February 6, 2020, 8:54am UTC](https://discourse.julialang.org/t/when-does-code-get-optimized-for-architecture/34213 "2020-02-06T08:54:10Z")

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My question might be a simple one: At what point (if at all) does julia code get optimized for the specific architecture it is running on? I dimly remember from some Juliacon talk that precompilation only lowers the cod…

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## [Hide long types in error output for better readability](https://discourse.julialang.org/t/hide-long-types-in-error-output-for-better-readability/32104)

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**Author:** [@Anderssorby](https://discourse.julialang.org/u/Anderssorby)\
**Replies:** 26\
**Last updated:** [February 5, 2020, 3:39pm UTC](https://discourse.julialang.org/t/hide-long-types-in-error-output-for-better-readability/32104 "2020-02-05T15:39:48Z")

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I am new to Julia and I like the language, but one thing I don’t like is the error messages. They are often a big block of mostly incomprehensible text which I suspect might scare some developers away. This is largely du…

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## [Taking the array indexing interface seriously](https://discourse.julialang.org/t/taking-the-array-indexing-interface-seriously/32035)

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**Author:** [@Raf](https://discourse.julialang.org/u/Raf)\
**Replies:** 31\
**Last updated:** [February 3, 2020, 3:16pm UTC](https://discourse.julialang.org/t/taking-the-array-indexing-interface-seriously/32035 "2020-02-03T15:16:13Z")

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I’m doing some work standardizing array interfaces for the spatial data ecosystem in HDF5, ArchGDAL and in GeoData. It’s not uncommon for widely use packages to have non-standard indexing inputs and outputs. HDF5.jl cu…

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## [Julia Roadmap](https://discourse.julialang.org/t/julia-roadmap/33998)

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**Author:** [@digeratus](https://discourse.julialang.org/u/digeratus)\
**Replies:** 20\
**Last updated:** [February 2, 2020, 7:21am UTC](https://discourse.julialang.org/t/julia-roadmap/33998 "2020-02-02T07:21:03Z")

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Other lang communities have public roadmaps e.g. rust, go, ruby, etc I’m wondering if there’s a version for Julia I can take a look. It would help immensely, particularly in terms of transparency, community, etc. Thanks. …

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## [Using reserved words/syntax (try, ?) as macro names](https://discourse.julialang.org/t/using-reserved-words-syntax-try-as-macro-names/34063)

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**Author:** [@kevin.squire](https://discourse.julialang.org/u/kevin.squire)\
**Replies:** 2\
**Last updated:** [February 1, 2020, 4:15pm UTC](https://discourse.julialang.org/t/using-reserved-words-syntax-try-as-macro-names/34063 "2020-02-01T16:15:11Z")

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TL;DR: I’d like to be able to use @try or @? as macro names for try-catch-like syntax in code using Result types. Would this be reasonable to allow? ############ I’ve been exploring ResultTypes.jl as an alternative to…

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## [\\circ and parantheses](https://discourse.julialang.org/t/circ-and-parantheses/18196)

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**Author:** [@BeastyBlacksmith](https://discourse.julialang.org/u/BeastyBlacksmith)\
**Replies:** 9\
**Last updated:** [January 27, 2020, 8:17pm UTC](https://discourse.julialang.org/t/circ-and-parantheses/18196 "2020-01-27T20:17:14Z")

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The main thing that causes me to not use the \\circ operator in julia as much as i do the mathematica equivalent (they use @) is, that I need to wrap everything in parantheses. I can see that this relates nicely to mathe…

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## [Status of waiting on multiple conditions / @select](https://discourse.julialang.org/t/status-of-waiting-on-multiple-conditions-select/33867)

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**Author:** [@bachdavid](https://discourse.julialang.org/u/bachdavid)\
**Replies:** 0\
**Last updated:** [January 27, 2020, 6:10pm UTC](https://discourse.julialang.org/t/status-of-waiting-on-multiple-conditions-select/33867 "2020-01-27T18:10:02Z")

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Hi everyone, wanted to say hi and see what the current status of waiting on multiple conditions is. Currently, I am using two channels, and I’d like to wait for either of them having a pending put!. There exists a PR …

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## [Anonymous nested struct](https://discourse.julialang.org/t/anonymous-nested-struct/33723)

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**Author:** [@Sijun](https://discourse.julialang.org/u/Sijun)\
**Replies:** 12\
**Last updated:** [January 26, 2020, 5:53pm UTC](https://discourse.julialang.org/t/anonymous-nested-struct/33723 "2020-01-26T17:53:06Z")

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By “Anonymous nested struct” I mean defining a struct that has another struct with no name inside: struct ABC name::String data::struct raw::Vector{Float64} value::Int end end I wonder such …

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## [Swizzling the super type of a foreign Julia type (or: how evil must I be?)](https://discourse.julialang.org/t/swizzling-the-super-type-of-a-foreign-julia-type-or-how-evil-must-i-be/33733)

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**Author:** [@fingolfin](https://discourse.julialang.org/u/fingolfin)\
**Replies:** 2\
**Last updated:** [January 24, 2020, 8:48pm UTC](https://discourse.julialang.org/t/swizzling-the-super-type-of-a-foreign-julia-type-or-how-evil-must-i-be/33733 "2020-01-24T20:48:17Z")

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Hi, so this is a super low-level question for the people who know about or are working on the Julia kernel. tl;dr I need/want to create a “foreign type” MPtr (via the C function jl\_new\_foreign\_type) with no super type,…

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## [Proposal: syntax for accessing arrays using relative indices](https://discourse.julialang.org/t/proposal-syntax-for-accessing-arrays-using-relative-indices/33699)

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**Author:** [@Ronis\_BR](https://discourse.julialang.org/u/Ronis_BR)\
**Replies:** 11\
**Last updated:** [January 24, 2020, 1:00am UTC](https://discourse.julialang.org/t/proposal-syntax-for-accessing-arrays-using-relative-indices/33699 "2020-01-24T01:00:35Z")

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Hi! Let’s say I want to access 4 elements of an array. Today, I do something like: data\[1200:1203\] data\[1200:1200+3\] or data\[i:i+3\] Wouldn’t be nice if we have a syntax to access elements using relative indices? Som…

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## [Atan(y,x) for complex numbers](https://discourse.julialang.org/t/atan-y-x-for-complex-numbers/33692)

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**Author:** [@arturgower](https://discourse.julialang.org/u/arturgower)\
**Replies:** 4\
**Last updated:** [January 23, 2020, 5:15pm UTC](https://discourse.julialang.org/t/atan-y-x-for-complex-numbers/33692 "2020-01-23T17:15:49Z")

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There doesn’t seem to be an implementation for atan when x and y are complex numbers. The currently implement atan(y/x) is not a replacement, as it loses the information on which quadrants x and y are in. This is import…

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## [Add \`if\` to for-loops like in comprehensions](https://discourse.julialang.org/t/add-if-to-for-loops-like-in-comprehensions/33632)

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**Author:** [@bjarthur](https://discourse.julialang.org/u/bjarthur)\
**Replies:** 5\
**Last updated:** [January 21, 2020, 7:55pm UTC](https://discourse.julialang.org/t/add-if-to-for-loops-like-in-comprehensions/33632 "2020-01-21T19:55:07Z")

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apologies if this has been discussed before, but i was surprised it didn’t work when i naively tried it: julia\> for i in 1:10 if i\>3 @info i end ERROR: syntax: incomplete: "for" at REPL\[1\]:1 requires end …

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## [RFC: Make an abstraction for custom task parallel schedulers (GSoC proposal)](https://discourse.julialang.org/t/rfc-make-an-abstraction-for-custom-task-parallel-schedulers-gsoc-proposal/33284)

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**Author:** [@s417-lama](https://discourse.julialang.org/u/s417-lama)\
**Replies:** 19\
**Last updated:** [January 20, 2020, 8:03pm UTC](https://discourse.julialang.org/t/rfc-make-an-abstraction-for-custom-task-parallel-schedulers-gsoc-proposal/33284 "2020-01-20T20:03:50Z")

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I’m currently thinking of applying for JSoC/GSoC, and I’d like to discuss a project for it, which is about task parallelism. As discussed in reduce overhead of task creation and switching · Issue #33762 · JuliaLang/juli…

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## [Should a view of a SharedArray be also shared between workers?](https://discourse.julialang.org/t/should-a-view-of-a-sharedarray-be-also-shared-between-workers/33580)

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**Author:** [@Gregstrq](https://discourse.julialang.org/u/Gregstrq)\
**Replies:** 3\
**Last updated:** [January 20, 2020, 1:23pm UTC](https://discourse.julialang.org/t/should-a-view-of-a-sharedarray-be-also-shared-between-workers/33580 "2020-01-20T13:23:15Z")

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Consider the following simple example, where we try to fill a view of a SharedArray on a worker (I’ve tested it on julia 1.1.0): using Distributed w = addprocs(1)\[\] using SharedArrays function idid!(v) for i=1:len…

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## [Parallel Mersenne Twister](https://discourse.julialang.org/t/parallel-mersenne-twister/27567)

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**Author:** [@cscherrer](https://discourse.julialang.org/u/cscherrer)\
**Replies:** 18\
**Last updated:** [January 19, 2020, 12:32pm UTC](https://discourse.julialang.org/t/parallel-mersenne-twister/27567 "2020-01-19T12:32:01Z")

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Like many people, I’m pretty excited about the new multithreading capabilities in 1.3. But there’s one thing in the announcement that I’m not sure about, so it seems worth some discussion. It says, The approach we’ve …

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## [Building thread-safe data structures](https://discourse.julialang.org/t/building-thread-safe-data-structures/33537)

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**Author:** [@Ali\_Mamdouh](https://discourse.julialang.org/u/Ali_Mamdouh)\
**Replies:** 0\
**Last updated:** [January 19, 2020, 8:03am UTC](https://discourse.julialang.org/t/building-thread-safe-data-structures/33537 "2020-01-19T08:03:08Z")

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i am thinking about start contributing to julia by writing some thread-safe data structures, i want to know what the to make to make my pull request get merged, e.g what the interface should, if you think of some languag…

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## [Improve type handling in skipmissing](https://discourse.julialang.org/t/improve-type-handling-in-skipmissing/33513)

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**Author:** [@Alex1](https://discourse.julialang.org/u/Alex1)\
**Replies:** 8\
**Last updated:** [January 19, 2020, 3:08am UTC](https://discourse.julialang.org/t/improve-type-handling-in-skipmissing/33513 "2020-01-19T03:08:19Z")

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Would be nice to improve skipmissing, maybe always apply collect? If the reason not to apply it is the performance, I would say - predictability and principle of least surprise is more important than performance. serie …

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## [What concurrency tools you think will be useful to add to julia?](https://discourse.julialang.org/t/what-concurrency-tools-you-think-will-be-useful-to-add-to-julia/33530)

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**Author:** [@Ali\_Mamdouh](https://discourse.julialang.org/u/Ali_Mamdouh)\
**Replies:** 2\
**Last updated:** [January 19, 2020, 1:48am UTC](https://discourse.julialang.org/t/what-concurrency-tools-you-think-will-be-useful-to-add-to-julia/33530 "2020-01-19T01:48:47Z")

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i am exciting to contribute to julia by implementing some concurrency tools, so i want some suggestions about things i can do.

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## [Any syntax to specify whether a function should or should not be compiled?](https://discourse.julialang.org/t/any-syntax-to-specify-whether-a-function-should-or-should-not-be-compiled/33125)

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**Author:** [@nxtruong](https://discourse.julialang.org/u/nxtruong)\
**Replies:** 9\
**Last updated:** [January 16, 2020, 7:18am UTC](https://discourse.julialang.org/t/any-syntax-to-specify-whether-a-function-should-or-should-not-be-compiled/33125 "2020-01-16T07:18:37Z")

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I’m converting from Matlab (and some Python) to Julia. Honestly the time-to-first-plot issue of Julia really bothers me frequently. I almost never plot anything in Julia for that reason; instead, I save my (not so large)…

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## [Why not make + and sum() operators between Booleans act as bitwise operators?](https://discourse.julialang.org/t/why-not-make-and-sum-operators-between-booleans-act-as-bitwise-operators/33350)

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**Author:** [@Emre\_Acarturk](https://discourse.julialang.org/u/Emre_Acarturk)\
**Replies:** 5\
**Last updated:** [January 14, 2020, 7:34pm UTC](https://discourse.julialang.org/t/why-not-make-and-sum-operators-between-booleans-act-as-bitwise-operators/33350 "2020-01-14T19:34:45Z")

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I feel like this change wouldn’t affect Julia in general, but AND and OR operation between Boolean variables are usually denoted as addition and multiplication and result in a Boolean. In its current implementation, sum(…

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## [New scope solution](https://discourse.julialang.org/t/new-scope-solution/16707)

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**Author:** [@StefanKarpinski](https://discourse.julialang.org/u/StefanKarpinski)\
**Replies:** 233\
**Last updated:** [January 14, 2020, 5:47pm UTC](https://discourse.julialang.org/t/new-scope-solution/16707 "2020-01-14T17:47:28Z")

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I have an alternate, non-breaking solution to the scope issue previously discussed on discourse and github. The new potential solution is the following rule to decide whether a variable, x, which is not marked as explici…

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