# Internals & Design

**URL:** https://discourse.julialang.org/c/dev/5.md?page=48

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**Page:** 49

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## [Building 1.1.0 on Raspberry PI 3B+ running Raspian](https://discourse.julialang.org/t/building-1-1-0-on-raspberry-pi-3b-running-raspian/22459)

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**Author:** [@PhotoNomad0](https://discourse.julialang.org/u/PhotoNomad0)\
**Replies:** 0\
**Last updated:** [March 28, 2019, 2:05pm UTC](https://discourse.julialang.org/t/building-1-1-0-on-raspberry-pi-3b-running-raspian/22459 "2019-03-28T14:05:11Z")

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I got quite far, but am stuck. What I have done up to this point: Installed the build tools. Did git clone and then checked out checkout tag v1.1.0. Did “make” and then “make binary-dist”. On “make binary-dist”, ran …

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## [How is destructuring transformed\\lowered](https://discourse.julialang.org/t/how-is-destructuring-transformed-lowered/22421)

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**Author:** [@ndinsmore](https://discourse.julialang.org/u/ndinsmore)\
**Replies:** 6\
**Last updated:** [March 27, 2019, 8:28pm UTC](https://discourse.julialang.org/t/how-is-destructuring-transformed-lowered/22421 "2019-03-27T20:28:21Z")

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I have seen it mentioned before that: function f((x,y)) is effectively transformed to function f(temp) x , y = temp But I don’t think that it is documented anywhere how x , y = temp is transformed. Could somebod…

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## [Division for Strings](https://discourse.julialang.org/t/division-for-strings/22381)

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**Author:** [@asprionj](https://discourse.julialang.org/u/asprionj)\
**Replies:** 6\
**Last updated:** [March 27, 2019, 6:52pm UTC](https://discourse.julialang.org/t/division-for-strings/22381 "2019-03-27T18:52:41Z")

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Just had this silly idea when trying to prepend a string to an existing one. When appending, one can do: a = "1" a \*= ",2" # "1,2" Now, we could use division for prepending: a = "1" a /= "0," # "0,1" What do you th…

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## [Move ASDF.jl to JuliaIO?](https://discourse.julialang.org/t/move-asdf-jl-to-juliaio/21637)

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**Author:** [@schnetter](https://discourse.julialang.org/u/schnetter)\
**Replies:** 16\
**Last updated:** [March 27, 2019, 2:00am UTC](https://discourse.julialang.org/t/move-asdf-jl-to-juliaio/21637 "2019-03-27T02:00:37Z")

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Would it make sense to move the ASDF package to JuliaIO? If so, how would I proceed? -erik

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## [RFC: a "workaround" for the multi-project precompilation cache problem without long-term code debt](https://discourse.julialang.org/t/rfc-a-workaround-for-the-multi-project-precompilation-cache-problem-without-long-term-code-debt/22233)

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**Author:** [@tkf](https://discourse.julialang.org/u/tkf)\
**Replies:** 18\
**Last updated:** [March 26, 2019, 11:23pm UTC](https://discourse.julialang.org/t/rfc-a-workaround-for-the-multi-project-precompilation-cache-problem-without-long-term-code-debt/22233 "2019-03-26T23:23:20Z")

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Many of us now realized that it is a pain to use multiple projects because switching projects invoke precompilation: I suggested a “workaround” a while ago but it never got much attention: So, allow me to advertise…

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## [RFC: Reference Iterator for better in place loop modifications](https://discourse.julialang.org/t/rfc-reference-iterator-for-better-in-place-loop-modifications/22312)

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**Author:** [@ndinsmore](https://discourse.julialang.org/u/ndinsmore)\
**Replies:** 4\
**Last updated:** [March 25, 2019, 7:40pm UTC](https://discourse.julialang.org/t/rfc-reference-iterator-for-better-in-place-loop-modifications/22312 "2019-03-25T19:40:36Z")

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Has there ever been any discussion of creating a RefsIterator type and the accompanying refs(collection) which returns a Ref to the values of a collection? So you could write: col=collect(1:1000) for r in refs(col) …

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## [Parametric inner constructor inherits parameter from global scope](https://discourse.julialang.org/t/parametric-inner-constructor-inherits-parameter-from-global-scope/22296)

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**Author:** [@bkamins](https://discourse.julialang.org/u/bkamins)\
**Replies:** 9\
**Last updated:** [March 25, 2019, 1:08pm UTC](https://discourse.julialang.org/t/parametric-inner-constructor-inherits-parameter-from-global-scope/22296 "2019-03-25T13:08:59Z")

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See Parametric composite type inner constructors in Julia: Why is \`where {T}\` necessary? - Stack Overflow for the original question. Now parametric inner constructor without where inherits its parameter from global scop…

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## [Future development goals with the new Revise](https://discourse.julialang.org/t/future-development-goals-with-the-new-revise/22298)

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**Author:** [@tim.holy](https://discourse.julialang.org/u/tim.holy)\
**Replies:** 0\
**Last updated:** [March 25, 2019, 11:47am UTC](https://discourse.julialang.org/t/future-development-goals-with-the-new-revise/22298 "2019-03-25T11:47:03Z")

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This is basically a reply to \[ANN\] Juno 0.8 - #23 by pfitzseb, but it also outlines a couple of projects that need doing in Revise. At the outset I should say that given other duties I’m unsure how quickly these will get…

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## [Why do we need the \`do\` keyword?](https://discourse.julialang.org/t/why-do-we-need-the-do-keyword/22236)

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**Author:** [@sagartewari01](https://discourse.julialang.org/u/sagartewari01)\
**Replies:** 13\
**Last updated:** [March 25, 2019, 9:25am UTC](https://discourse.julialang.org/t/why-do-we-need-the-do-keyword/22236 "2019-03-25T09:25:34Z")

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According to the documentation, all this keyword does is create a lambda and insert it as the first argument of function call before it. This task could be accomplished with a macro with very similar syntax: @do map(col…

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## [Measuring time of type inference](https://discourse.julialang.org/t/measuring-time-of-type-inference/22186)

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**Author:** [@juthohaegeman](https://discourse.julialang.org/u/juthohaegeman)\
**Replies:** 8\
**Last updated:** [March 25, 2019, 5:59am UTC](https://discourse.julialang.org/t/measuring-time-of-type-inference/22186 "2019-03-25T05:59:18Z")

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My package Strided.jl seems to give type inference a very hard time, which becomes even worse in packages that depend on it (like TensorOperations.jl). I know about packages like SnoopCompile.jl and PackageCompiler.jl, …

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## [Embedded Julia changes original standart streams?](https://discourse.julialang.org/t/embedded-julia-changes-original-standart-streams/22222)

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**Author:** [@mmmm1998](https://discourse.julialang.org/u/mmmm1998)\
**Replies:** 0\
**Last updated:** [March 22, 2019, 10:16pm UTC](https://discourse.julialang.org/t/embedded-julia-changes-original-standart-streams/22222 "2019-03-22T22:16:40Z")

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Hi, I development Qt application with embedded Julia (in some way). Main process with GUI (Client) starts another process with embedded Julia (server) via QProcess and working with the process via standart streams. All w…

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## [Reference on autocompletion](https://discourse.julialang.org/t/reference-on-autocompletion/22148)

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**Author:** [@JeffreySarnoff](https://discourse.julialang.org/u/JeffreySarnoff)\
**Replies:** 0\
**Last updated:** [March 21, 2019, 2:34pm UTC](https://discourse.julialang.org/t/reference-on-autocompletion/22148 "2019-03-21T14:34:55Z")

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@StefanKarpinski posted this in slack with the comment “… all Julia UIs should follow these rules”. I am reposting here for longevity. Rules for Autocomplete some highlights Exact matches always come first. Prefix m…

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## [Inconsistent behaviour of Diagonal and Triangular matrix constructors](https://discourse.julialang.org/t/inconsistent-behaviour-of-diagonal-and-triangular-matrix-constructors/22134)

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**Author:** [@bsxfan](https://discourse.julialang.org/u/bsxfan)\
**Replies:** 1\
**Last updated:** [March 21, 2019, 8:42am UTC](https://discourse.julialang.org/t/inconsistent-behaviour-of-diagonal-and-triangular-matrix-constructors/22134 "2019-03-21T08:42:26Z")

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Let e.g.: R=randn(2,2), (a general square matrix) then U = UpperTriangular(R) or L = LowerTriangular(R) would sucessfully return triangular matrices. Also, D = Diagonal(R) works similarly. In all these cases, some (in ge…

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## [Strange behavior in type system with Adjoint and DenseArray](https://discourse.julialang.org/t/strange-behavior-in-type-system-with-adjoint-and-densearray/22127)

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**Author:** [@raphbacher](https://discourse.julialang.org/u/raphbacher)\
**Replies:** 2\
**Last updated:** [March 21, 2019, 12:15am UTC](https://discourse.julialang.org/t/strange-behavior-in-type-system-with-adjoint-and-densearray/22127 "2019-03-21T00:15:38Z")

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Hi, I’m trying to tackle issue #24590 (https://github.com/JuliaLang/julia/issues/24590). To do so I want to add a method to deal with transpose/adjoint of dense vectors (to call BLAS.dotc). I don’t understand why the …

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## [The reason why the parameters for Distributions.Normal is mean and standard deviation](https://discourse.julialang.org/t/the-reason-why-the-parameters-for-distributions-normal-is-mean-and-standard-deviation/22088)

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**Author:** [@paalon](https://discourse.julialang.org/u/paalon)\
**Replies:** 6\
**Last updated:** [March 20, 2019, 2:48pm UTC](https://discourse.julialang.org/t/the-reason-why-the-parameters-for-distributions-normal-is-mean-and-standard-deviation/22088 "2019-03-20T14:48:50Z")

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I have fallen into a stagnation of my work due to the normal distribution of the package Distributions need to be specified its mean and standard deviation but I have assumed that mean and variance because most of the ma…

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## [Expand a Tuple at given positions, type stable dims](https://discourse.julialang.org/t/expand-a-tuple-at-given-positions-type-stable-dims/21914)

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**Author:** [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)\
**Replies:** 8\
**Last updated:** [March 18, 2019, 9:10pm UTC](https://discourse.julialang.org/t/expand-a-tuple-at-given-positions-type-stable-dims/21914 "2019-03-18T21:10:56Z")

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I would like to make a PR extending #29749 by generalizing eachslice to generic dimensions. I have two questions: What’s the recommended API for specifying dimensions in a type stable way? Eg should I use a Tuple of V…

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## [REQUIRE vs Project.toml](https://discourse.julialang.org/t/require-vs-project-toml/21962)

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**Author:** [@bjarthur](https://discourse.julialang.org/u/bjarthur)\
**Replies:** 1\
**Last updated:** [March 17, 2019, 12:40pm UTC](https://discourse.julialang.org/t/require-vs-project-toml/21962 "2019-03-17T12:40:45Z")

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can someone please remind me whether packages currently need one or the other or both to work on 0.7/1? it doesn’t seem to be documented, and my slack history doesn’t go back far enough to look up the answer when i aske…

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## [Base.@kwdef for v1.0?](https://discourse.julialang.org/t/base-kwdef-for-v1-0/21954)

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**Author:** [@anon67531922](https://discourse.julialang.org/u/anon67531922)\
**Replies:** 12\
**Last updated:** [March 17, 2019, 12:03pm UTC](https://discourse.julialang.org/t/base-kwdef-for-v1-0/21954 "2019-03-17T12:03:41Z")

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Hi :wave: I stumbled on Base.@kwdef on Julia v1.1 and find it quite helpful and reduces a ton of boilerplate for my large types with lots of default values. I started using it in my packages, but tests fail on Julia v1…

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## [Cchar != eltype(Cstring)](https://discourse.julialang.org/t/cchar-eltype-cstring/21634)

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**Author:** [@nstiurca](https://discourse.julialang.org/u/nstiurca)\
**Replies:** 2\
**Last updated:** [March 17, 2019, 11:10am UTC](https://discourse.julialang.org/t/cchar-eltype-cstring/21634 "2019-03-17T11:10:56Z")

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So I am wrapping some C libraries in Julia, and noticed that Cchar maps to Int8, whereas Cstring has an eltype of UInt8, calling pointer(some\_cstring) returns a Ptr{UInt8}. This inconsistency seems rather odd. Furthermor…

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## [Serializing multiple values](https://discourse.julialang.org/t/serializing-multiple-values/17205)

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**Author:** [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)\
**Replies:** 4\
**Last updated:** [March 16, 2019, 8:39am UTC](https://discourse.julialang.org/t/serializing-multiple-values/17205 "2019-03-16T08:39:07Z")

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The documentation for Serialization is pretty sparse, and I am wondering if I am using it correctly. I will write up what I learn here as a PR for the docs. I want to serialize multiple objects to a stream from an itera…

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## [\`try\` blocks, improving their docs](https://discourse.julialang.org/t/try-blocks-improving-their-docs/21917)

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**Author:** [@JeffreySarnoff](https://discourse.julialang.org/u/JeffreySarnoff)\
**Replies:** 10\
**Last updated:** [March 16, 2019, 6:29am UTC](https://discourse.julialang.org/t/try-blocks-improving-their-docs/21917 "2019-03-16T06:29:55Z")

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Let’s document the in’s and out’s of try \[catch\] \[finally\] end blocks, and the use\[s\] of each part, the purpose of rethrow and why one would choose to include or exclude either the catch part or the finally part or both.…

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## [stdlib dateformat parsing is inconsistent, creates 32-bit issue](https://discourse.julialang.org/t/stdlib-dateformat-parsing-is-inconsistent-creates-32-bit-issue/21886)

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**Author:** [@fchorney](https://discourse.julialang.org/u/fchorney)\
**Replies:** 3\
**Last updated:** [March 15, 2019, 9:59pm UTC](https://discourse.julialang.org/t/stdlib-dateformat-parsing-is-inconsistent-creates-32-bit-issue/21886 "2019-03-15T21:59:25Z")

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The tl;dr of this is that when julia does DateTime parsing, it tends to cast any resulting int values to Int64 (year, month, day, etc). Specifically on the “u” or “U” dateformat (which is either abbreviated month i.e. ja…

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## [Function to check all arguments are the same and return their value](https://discourse.julialang.org/t/function-to-check-all-arguments-are-the-same-and-return-their-value/21253)

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**Author:** [@mfsch](https://discourse.julialang.org/u/mfsch)\
**Replies:** 12\
**Last updated:** [March 15, 2019, 8:45pm UTC](https://discourse.julialang.org/t/function-to-check-all-arguments-are-the-same-and-return-their-value/21253 "2019-03-15T20:45:44Z")

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I’ve observed that I often encounter this pattern where I have several ways of getting a value I need that should be equivalent. The most typical case is getting some array dimension. function f(data, x, y, z) nx = …

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## [METADATA vs Registry](https://discourse.julialang.org/t/metadata-vs-registry/21688)

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**Author:** [@OliverEvans96](https://discourse.julialang.org/u/OliverEvans96)\
**Replies:** 4\
**Last updated:** [March 11, 2019, 12:28am UTC](https://discourse.julialang.org/t/metadata-vs-registry/21688 "2019-03-11T00:28:36Z")

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Hi all, In the v0.6 documentation, there’s a section about maintaining a custom metadata repository. That section seems to have disappeared in the v1.0, and the Pkg.init command is not present in Pkg3. In the v1.1, this…

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## [Allow redefining functions names of outer scope? ERROR: UndefVarError: f not defined](https://discourse.julialang.org/t/allow-redefining-functions-names-of-outer-scope-error-undefvarerror-f-not-defined/21676)

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**Author:** [@schlichtanders](https://discourse.julialang.org/u/schlichtanders)\
**Replies:** 9\
**Last updated:** [March 10, 2019, 4:53pm UTC](https://discourse.julialang.org/t/allow-redefining-functions-names-of-outer-scope-error-undefvarerror-f-not-defined/21676 "2019-03-10T16:53:50Z")

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It seems we have to use reflections in order to overwrite a function from an outer scope. Please look at the following minimal example module MyModule f(a) = a function f2() h = getfield(MyModule, :f) #= i…

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## [New syntax for multi-line macrocalls](https://discourse.julialang.org/t/new-syntax-for-multi-line-macrocalls/21571)

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**Author:** [@Evey](https://discourse.julialang.org/u/Evey)\
**Replies:** 3\
**Last updated:** [March 7, 2019, 8:33pm UTC](https://discourse.julialang.org/t/new-syntax-for-multi-line-macrocalls/21571 "2019-03-07T20:33:18Z")

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Hi! :smile: This is a proposal for an additional macrocall syntax which will parse past newlines until an end is encountered. The idea is to have a syntax which allows using a macro more akin to reserved keyword blocks …

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## [Pattern matching for macros](https://discourse.julialang.org/t/pattern-matching-for-macros/21583)

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**Author:** [@Evey](https://discourse.julialang.org/u/Evey)\
**Replies:** 4\
**Last updated:** [March 7, 2019, 5:53pm UTC](https://discourse.julialang.org/t/pattern-matching-for-macros/21583 "2019-03-07T17:53:31Z")

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I know that I have brought this up a number of times in these forums, so I hope I’m not becoming annoying, but I can’t help but feel that this falls well short of addressing the real problem of lacking proper pattern mat…

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## [REPL's own scope](https://discourse.julialang.org/t/repls-own-scope/21365)

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**Author:** [@jeffe](https://discourse.julialang.org/u/jeffe)\
**Replies:** 3\
**Last updated:** [March 3, 2019, 7:31pm UTC](https://discourse.julialang.org/t/repls-own-scope/21365 "2019-03-03T19:31:45Z")

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Sorry for the new thread, trying not to litter @StefanKarpinski 's new scope solution, which this tangents from. Just two simple questions. I come to Julia with an understanding of scope in other languages, but… Th…

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## [Pkg/News info](https://discourse.julialang.org/t/pkg-news-info/21318)

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**Author:** [@Paul\_Soderlind](https://discourse.julialang.org/u/Paul_Soderlind)\
**Replies:** 2\
**Last updated:** [March 1, 2019, 12:58pm UTC](https://discourse.julialang.org/t/pkg-news-info/21318 "2019-03-01T12:58:31Z")

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I believe that the package manager should (optionally) show a short “News” for each package that is updated. Example: package X is updated, and the developer knows that this will cause issues in package Y but plans to f…

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## [Build julia without running the test suite](https://discourse.julialang.org/t/build-julia-without-running-the-test-suite/21282)

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**Author:** [@ulysses](https://discourse.julialang.org/u/ulysses)\
**Replies:** 3\
**Last updated:** [February 28, 2019, 3:39am UTC](https://discourse.julialang.org/t/build-julia-without-running-the-test-suite/21282 "2019-02-28T03:39:09Z")

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Hello! At some point, building Julia from sources (with make) began to imply running the test suite at the end. Is there a secret spell allowing to skip the tests?

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