# General Usage

**URL:** https://discourse.julialang.org/c/usage/6.md?page=956

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**Page:** 957

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## [0.7 \] How to list available packages](https://discourse.julialang.org/t/0-7-how-to-list-available-packages/13124)

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**Author:** [@Perrin\_Meyer](https://discourse.julialang.org/u/Perrin_Meyer)\
**Replies:** 3\
**Last updated:** [August 10, 2018, 12:34am UTC](https://discourse.julialang.org/t/0-7-how-to-list-available-packages/13124 "2018-08-10T00:34:18Z")

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I just downloaded and built Julia 0.7 I cant figure out how to get the new package manager \] to list available packages? (I was able to install PyPlot and FFTW, but I know those names by heart). I’ve looked through th…

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## [What's the official procedure for tagging release in new Pkg manager?](https://discourse.julialang.org/t/whats-the-official-procedure-for-tagging-release-in-new-pkg-manager/13130)

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**Author:** [@chakravala](https://discourse.julialang.org/u/chakravala)\
**Replies:** 2\
**Last updated:** [August 10, 2018, 12:16am UTC](https://discourse.julialang.org/t/whats-the-official-procedure-for-tagging-release-in-new-pkg-manager/13130 "2018-08-10T00:16:54Z")

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Trying to understand how to tag a new release from within 1.0 with the new package manager.

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## [Segmentation fault on 0.7](https://discourse.julialang.org/t/segmentation-fault-on-0-7/13065)

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**Author:** [@bernhard](https://discourse.julialang.org/u/bernhard)\
**Replies:** 3\
**Last updated:** [August 9, 2018, 9:47pm UTC](https://discourse.julialang.org/t/segmentation-fault-on-0-7/13065 "2018-08-09T21:47:09Z")

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I am getting a segmentation fault during tests (line 974). Any ideas how I can find the cause? The tests worked fine on beta2 Also, for some deprecation warnings (e.g. line 949 WARNING: Base.ObjectIdDict is deprecat…

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## [Test errors in Julia v0.7](https://discourse.julialang.org/t/test-errors-in-julia-v0-7/13118)

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**Author:** [@Ronis\_BR](https://discourse.julialang.org/u/Ronis_BR)\
**Replies:** 2\
**Last updated:** [August 9, 2018, 9:36pm UTC](https://discourse.julialang.org/t/test-errors-in-julia-v0-7/13118 "2018-08-09T21:36:06Z")

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Hi guys, I am seeing this error in the tests using julia v0.7: Error in testset Sockets: Error During Test at /usr/share/julia/stdlib/v0.7/Sockets/test/runtests.jl:228 Got exception Base.IOError("UDP send failed: net…

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## [Coveralls showing NaN](https://discourse.julialang.org/t/coveralls-showing-nan/13112)

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**Author:** [@Ronis\_BR](https://discourse.julialang.org/u/Ronis_BR)\
**Replies:** 2\
**Last updated:** [August 9, 2018, 8:32pm UTC](https://discourse.julialang.org/t/coveralls-showing-nan/13112 "2018-08-09T20:32:27Z")

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Hi guys, Today I noticed that Coveralls is showing NaN to a folder. In this folder, I am not testing any of the functions. Is it a problem with Coveralls or Julia script that send data to Coveralls?

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## [Julia v0.7 requiring unversioned .so files](https://discourse.julialang.org/t/julia-v0-7-requiring-unversioned-so-files/13115)

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**Author:** [@Ronis\_BR](https://discourse.julialang.org/u/Ronis_BR)\
**Replies:** 0\
**Last updated:** [August 9, 2018, 8:31pm UTC](https://discourse.julialang.org/t/julia-v0-7-requiring-unversioned-so-files/13115 "2018-08-09T20:31:34Z")

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Hi guys, I am finishing the openSUSE package of Julia 0.7. However, I noticed a strange thing. Julia is requiring unversioned libraries to be placed at /usr/lib64/julia/, such as /usr/lib64/julia/libamd.so. Is this corr…

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## [Efficiently updating values in a sparse diagonal matrix](https://discourse.julialang.org/t/efficiently-updating-values-in-a-sparse-diagonal-matrix/13111)

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**Author:** [@Norman](https://discourse.julialang.org/u/Norman)\
**Replies:** 2\
**Last updated:** [August 9, 2018, 7:50pm UTC](https://discourse.julialang.org/t/efficiently-updating-values-in-a-sparse-diagonal-matrix/13111 "2018-08-09T19:50:41Z")

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Let’s say I have 5 vectors A, B, C, D, E and I build a sparse matrix as follows: M = spdiagm(0 =\> A, -1 =\> B, 1 =\> C, -10 =\> D, 10 =\> E) So, as you see, all the nonzero entries are on the five diagonals. (So, the numbe…

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## [V0.7.0 or v1.0.0?](https://discourse.julialang.org/t/v0-7-0-or-v1-0-0/13101)

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**Author:** [@rickhg12hs](https://discourse.julialang.org/u/rickhg12hs)\
**Replies:** 3\
**Last updated:** [August 9, 2018, 5:57pm UTC](https://discourse.julialang.org/t/v0-7-0-or-v1-0-0/13101 "2018-08-09T17:57:55Z")

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I see both v0.7.0 and v1.0.0 tags are both available. I’m on v0.6.4. Should I just go straight to v1.0.0? Are there some “migration” instructions? E.g., I see that v0.7.0 (and presumably v1.0.0) has different package…

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## [Possible bug: Crash during inference in @testset](https://discourse.julialang.org/t/possible-bug-crash-during-inference-in-testset/13108)

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**Author:** [@phlavenk](https://discourse.julialang.org/u/phlavenk)\
**Replies:** 0\
**Last updated:** [August 9, 2018, 4:15pm UTC](https://discourse.julialang.org/t/possible-bug-crash-during-inference-in-testset/13108 "2018-08-09T16:15:52Z")

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I’m encountering a crash of my streaming (point-by-point with no temporary arrays) FIR code (max speed wanted), appearing only when inside a @testset region. The error is clearly located in the Core.Inference of the Juli…

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## [Should failure to import be an error, not a warning?](https://discourse.julialang.org/t/should-failure-to-import-be-an-error-not-a-warning/13096)

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**Author:** [@cce](https://discourse.julialang.org/u/cce)\
**Replies:** 1\
**Last updated:** [August 9, 2018, 3:32pm UTC](https://discourse.julialang.org/t/should-failure-to-import-be-an-error-not-a-warning/13096 "2018-08-09T15:32:21Z")

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I noticed today that importing a name that’s not found in a module is a warning. Shouldn’t this be an error? julia\> import Base: start, next, done WARNING: could not import Base.start into Main WARNING: could not impo…

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## [0.7 "using" statement](https://discourse.julialang.org/t/0-7-using-statement/13104)

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**Author:** [@austinbean](https://discourse.julialang.org/u/austinbean)\
**Replies:** 0\
**Last updated:** [August 9, 2018, 3:28pm UTC](https://discourse.julialang.org/t/0-7-using-statement/13104 "2018-08-09T15:28:27Z")

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I have a bunch of types, structs and functions in a file I called ProjectModule.jl Something like: module ProjectModule using DataFrames abstract type A end mutable struct foo \<: A a::Int64 end …

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## [Julia for MATLAB users club](https://discourse.julialang.org/t/julia-for-matlab-users-club/12872)

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**Author:** [@airpmb](https://discourse.julialang.org/u/airpmb)\
**Replies:** 12\
**Last updated:** [August 9, 2018, 2:55pm UTC](https://discourse.julialang.org/t/julia-for-matlab-users-club/12872 "2018-08-09T14:55:18Z")

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… or maybe: posse? armada? crew? gang? task force? K-Pop group? :stuck\_out\_tongue: Continuing the discussion from Why \`eye\` has been deprecated?: ^ I proposed some sort of SIG for MATLAB users who like me are coming fr…

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## [Julia 0.7 : how to use iterate() to remove warning in Combinatorics.Combinations?](https://discourse.julialang.org/t/julia-0-7-how-to-use-iterate-to-remove-warning-in-combinatorics-combinations/13089)

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**Author:** [@Fred](https://discourse.julialang.org/u/Fred)\
**Replies:** 3\
**Last updated:** [August 9, 2018, 1:49pm UTC](https://discourse.julialang.org/t/julia-0-7-how-to-use-iterate-to-remove-warning-in-combinatorics-combinations/13089 "2018-08-09T13:49:38Z")

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Hi ! In Julia 0.7, the following code produce no error in the REPL julia\> using Combinatorics julia\> for c in Combinatorics.Combinations(1:3,2) println(c) end \[1, 2\] \[1, 3\] \[2, 3\] If I execute the co…

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## [0.7: The call to compilecache failed to create a usable precompiled cache](https://discourse.julialang.org/t/0-7-the-call-to-compilecache-failed-to-create-a-usable-precompiled-cache/13094)

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**Author:** [@LeoK987](https://discourse.julialang.org/u/LeoK987)\
**Replies:** 0\
**Last updated:** [August 9, 2018, 1:45pm UTC](https://discourse.julialang.org/t/0-7-the-call-to-compilecache-failed-to-create-a-usable-precompiled-cache/13094 "2018-08-09T13:45:26Z")

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Everytime I start julia, packages need to be precompiled again. What is wrong? $ julia \_ \_ \_ \_(\_)\_ | A fresh approach to technical computing (\_) | (\_) (\_) | Documentation: https:/…

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## [For loop globals in 0.7](https://discourse.julialang.org/t/for-loop-globals-in-0-7/13083)

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**Author:** [@gideonsimpson](https://discourse.julialang.org/u/gideonsimpson)\
**Replies:** 1\
**Last updated:** [August 9, 2018, 12:23pm UTC](https://discourse.julialang.org/t/for-loop-globals-in-0-7/13083 "2018-08-09T12:23:04Z")

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Can someone help me understand why the following loop has a deprecation warning in 0.7? julia\> t = 0.0; julia\> for j=1:10 t += 0.1; end ┌ Warning: Deprecated syntax \`implicit assignment to global vari…

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## [Rmath and Libdl dependency on v0.7](https://discourse.julialang.org/t/rmath-and-libdl-dependency-on-v0-7/13080)

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**Author:** [@colintbowers](https://discourse.julialang.org/u/colintbowers)\
**Replies:** 0\
**Last updated:** [August 9, 2018, 11:01am UTC](https://discourse.julialang.org/t/rmath-and-libdl-dependency-on-v0-7/13080 "2018-08-09T11:01:46Z")

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Hi all, I just downloaded the latest v0.7 binary for Linux 64 bit (2018-08-08 06:46 UTC). I deleted the contents of .julia and then added Rmath. The package added without a problem, but when I try and run it with using …

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## [0.7 deprecated warning does not go away](https://discourse.julialang.org/t/0-7-deprecated-warning-does-not-go-away/13063)

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**Author:** [@LeoK987](https://discourse.julialang.org/u/LeoK987)\
**Replies:** 4\
**Last updated:** [August 9, 2018, 6:03am UTC](https://discourse.julialang.org/t/0-7-deprecated-warning-does-not-go-away/13063 "2018-08-09T06:03:50Z")

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julia\> mean(A) WARNING: Base.mean is deprecated: it has been moved to the standard library package Statistics. Add using Statistics to your imports. in module Main 5.5 julia\> using Statistics julia\> mean(A) WARNIN…

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## [JunoIDE REPL ERROR: LoadError: Failed to precompile Juno (MacOS 10.13, Julia 1.0rc)](https://discourse.julialang.org/t/junoide-repl-error-loaderror-failed-to-precompile-juno-macos-10-13-julia-1-0rc/13062)

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**Author:** [@sdwarak](https://discourse.julialang.org/u/sdwarak)\
**Replies:** 1\
**Last updated:** [August 9, 2018, 6:03am UTC](https://discourse.julialang.org/t/junoide-repl-error-loaderror-failed-to-precompile-juno-macos-10-13-julia-1-0rc/13062 "2018-08-09T06:03:48Z")

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Stacktrace: Press Enter to start Julia. Starting Julia… \[ Info: Precompiling Atom \[c52e3926-4ff0-5f6e-af25-54175e0327b1\] ERROR: LoadError: LoadError: MethodError: no method matching eval(::Module, ::Expr) You may ha…

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## [How does one easily replace "contains" with "occursin"?](https://discourse.julialang.org/t/how-does-one-easily-replace-contains-with-occursin/13059)

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**Author:** [@LeoK987](https://discourse.julialang.org/u/LeoK987)\
**Replies:** 1\
**Last updated:** [August 9, 2018, 5:25am UTC](https://discourse.julialang.org/t/how-does-one-easily-replace-contains-with-occursin/13059 "2018-08-09T05:25:40Z")

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“contains” is deprecated in 0.7, but the arguments in the new “occursin” are reversed, making it uneasy to do a replacement.

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## [Is julia strongly checked(typed)?](https://discourse.julialang.org/t/is-julia-strongly-checked-typed/12990)

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**Author:** [@songtianyi](https://discourse.julialang.org/u/songtianyi)\
**Replies:** 7\
**Last updated:** [August 8, 2018, 5:08pm UTC](https://discourse.julialang.org/t/is-julia-strongly-checked-typed/12990 "2018-08-08T17:08:36Z")

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Is julia a strongly checked language, which means the type system prevent the untrapped error as more as possible? For example, C/C++ do allow pointer arithmetic operations, so they are not. If it is, what julia did to…

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## [DataFrames still not compile under Julia 0.7](https://discourse.julialang.org/t/dataframes-still-not-compile-under-julia-0-7/13052)

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**Author:** [@LeoK987](https://discourse.julialang.org/u/LeoK987)\
**Replies:** 2\
**Last updated:** [August 9, 2018, 2:41am UTC](https://discourse.julialang.org/t/dataframes-still-not-compile-under-julia-0-7/13052 "2018-08-09T02:41:46Z")

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There is an error compiling DataArrays: ERROR: LoadError: LoadError: UndefVarError: ipermute!! not defined But it looks that DataArrays is not being worked on for quite some long time. Any chance DataFrames can work…

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## [Extract a subarray from an array by eliminating certain rows and columns](https://discourse.julialang.org/t/extract-a-subarray-from-an-array-by-eliminating-certain-rows-and-columns/12974)

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**Author:** [@Norman](https://discourse.julialang.org/u/Norman)\
**Replies:** 4\
**Last updated:** [August 9, 2018, 12:20am UTC](https://discourse.julialang.org/t/extract-a-subarray-from-an-array-by-eliminating-certain-rows-and-columns/12974 "2018-08-09T00:20:55Z")

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I have two one-dimensional arrays, R and C. R is the row numbers and C is the column numbers. I need to get a subarray from an array A such that the new array does NOT contain certain rows and columns in A based on R and…

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## [Need data-storage package for 0.7 (JLD no longer working)](https://discourse.julialang.org/t/need-data-storage-package-for-0-7-jld-no-longer-working/11405)

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**Author:** [@Stephen\_Vavasis](https://discourse.julialang.org/u/Stephen_Vavasis)\
**Replies:** 18\
**Last updated:** [August 8, 2018, 10:11pm UTC](https://discourse.julialang.org/t/need-data-storage-package-for-0-7-jld-no-longer-working/11405 "2018-08-08T22:11:34Z")

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I have been using the JLD package for quite some time (since 0.4) to save and checkpoint my data that is shared between Linux and Windows. Right now, neither JLD nor JLD2 is working for Julia 0.7 (Windows). I suppose I…

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## [Enum tag collision](https://discourse.julialang.org/t/enum-tag-collision/13047)

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**Author:** [@Antigonus](https://discourse.julialang.org/u/Antigonus)\
**Replies:** 2\
**Last updated:** [August 8, 2018, 8:24pm UTC](https://discourse.julialang.org/t/enum-tag-collision/13047 "2018-08-08T20:24:13Z")

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julia\> @enum( Fruit, apple, orange, banana) julia\> @enum( Color, red, orange, blue) ERROR: invalid redefinition of constant orange I have many enums in a program at the same scope, and the program might even be autogene…

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## [Optimization of array views](https://discourse.julialang.org/t/optimization-of-array-views/13044)

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**Author:** [@aashish01](https://discourse.julialang.org/u/aashish01)\
**Replies:** 6\
**Last updated:** [August 8, 2018, 7:42pm UTC](https://discourse.julialang.org/t/optimization-of-array-views/13044 "2018-08-08T19:42:07Z")

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Consider the following code A = rand(1000,20); res = zeros(size(A,1)); @time for i in 1:size(A,1) p = view(A, i, :) res\[i\] = sum(p) end 0.004405 seconds (21.94 k allocations: 436.531 KiB) Note the number of allocati…

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## [WARNING: Base.Pkg is deprecated in 0.7 release](https://discourse.julialang.org/t/warning-base-pkg-is-deprecated-in-0-7-release/13038)

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**Author:** [@gideonsimpson](https://discourse.julialang.org/u/gideonsimpson)\
**Replies:** 17\
**Last updated:** [August 8, 2018, 6:10pm UTC](https://discourse.julialang.org/t/warning-base-pkg-is-deprecated-in-0-7-release/13038 "2018-08-08T18:10:07Z")

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I just installed the released 0.7 on MacOS, and whenever I try to install packages, I see the message: julia\> Pkg.add("IJulia") WARNING: Base.Pkg is deprecated, run \`using Pkg\` instead in module Main Is this simply on…

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## [Garbage collection of objects created in between gc\_enable(0) and gc\_enable(1)](https://discourse.julialang.org/t/garbage-collection-of-objects-created-in-between-gc-enable-0-and-gc-enable-1/11923)

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**Author:** [@vitreo12](https://discourse.julialang.org/u/vitreo12)\
**Replies:** 19\
**Last updated:** [August 8, 2018, 11:08am UTC](https://discourse.julialang.org/t/garbage-collection-of-objects-created-in-between-gc-enable-0-and-gc-enable-1/11923 "2018-08-08T11:08:31Z")

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Hello everyone, I have some embedded Julia code in C++ where I absolutely need that no gc is triggered under the hood. Could I disable the gc and re-enable soon after? Would this mean that, if some temporary buffers or …

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## [Evaluation of string with local variable](https://discourse.julialang.org/t/evaluation-of-string-with-local-variable/12713)

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**Author:** [@economyboy](https://discourse.julialang.org/u/economyboy)\
**Replies:** 5\
**Last updated:** [August 8, 2018, 10:55am UTC](https://discourse.julialang.org/t/evaluation-of-string-with-local-variable/12713 "2018-08-08T10:55:16Z")

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I have strings in context of symbolic diffferentiation. Therefore I need to evaluate strings which contain local variables. In the manual to Metaprogramming is this example: macro zerox() return esc(:(x = 0)) end fu…

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## [Error in a parallel loop in Julia 0.7 rc2](https://discourse.julialang.org/t/error-in-a-parallel-loop-in-julia-0-7-rc2/12925)

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**Author:** [@Alexander-Barth](https://discourse.julialang.org/u/Alexander-Barth)\
**Replies:** 2\
**Last updated:** [August 8, 2018, 10:01am UTC](https://discourse.julialang.org/t/error-in-a-parallel-loop-in-julia-0-7-rc2/12925 "2018-08-08T10:01:29Z")

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Since Julia version 0.7.0-rc2, I have an error in a parallel loop. Unfortunately, I am not able to narrow this error down to a minimum code snippet. The error message (from a clean julia restart) is every time differen…

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## [Bug or wrong usage of @static in 0.7RC2?](https://discourse.julialang.org/t/bug-or-wrong-usage-of-static-in-0-7rc2/12917)

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**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 6\
**Last updated:** [August 8, 2018, 8:46am UTC](https://discourse.julialang.org/t/bug-or-wrong-usage-of-static-in-0-7rc2/12917 "2018-08-08T08:46:23Z")

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The following code (part of ModiaMath.jl) fails on 0.7: julia\> @static if VERSION \< v"0.7.0-DEV.2005" print(" \\# ") else print(" # ") end ERROR: syntax: invalid escape sequence A…

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