Julia 0.5.0 发布，动态编程语言

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　　Julia 0.5.0 发布了，本次更新包括了很多新的语言特性。
　　Julia是一个新的高性能动态高级编程语言。语法和其他编程语言类似，易于其他语言用户学习。Julia拥有丰富的函数库，提供了数字精度、精致的增幅 器（sophisticated amplifier）和分布式并行运行方式。核心函数库等大多数库是由Julia编写，但也用成熟的C和FORTRAN库来处理线性代数、随机数产生和字 符串处理等问题。Julia语言可定义函数并且根据用户自定义的参数类型组合再进行重载。
　　部分更新内容如下：

• 　　Generator expressions: `f(i) for i in 1:n` ([#4470]). This returns an iterator that computes the specified values on demand. This is useful for computing, e.g.
  
• 　　`sum(f(i) for i in 1:n)` without creating an intermediate array of values.
  
• 　　Generators and comprehensions support filtering using `if` ([#550]) and nested iteration using multiple `for` keywords ([#4867]).
  
• 　　Fused broadcasting syntax: ``f.(args...)`` is equivalent to ``broadcast(f, args...)`` ([#15032]), and nested `f.(g.(args...))` calls are fused into a single `broadcast` loop ([#17300]).
  
• 　　Similarly, the syntax `x .= ...` is equivalent to a `broadcast!(identity, x, ...)`call and fuses with nested "dot" calls; also, `x .+= y` and similar is now equivalent to `x .= x .+ y`, rather than `x = x .+ y` ([#17510]).
  
• 　　Macro expander functions are now generic, so macros can have multiple definitions(e.g. for different numbers of arguments, or optional arguments) ([#8846], [#9627]).
  
• 　　However note that the argument types refer to the syntax tree representation, and not to the types of run time values.
  
• 　　Varargs functions like `foo{T}(x::T...)` may now restrict the number of such arguments using `foo{T,N}(x::Vararg{T,N})` ([#11242]).
  
• 　　`x ∈ X` is now a synonym for `x in X` in `for` loops and comprehensions, as it already was in comparisons ([#13824]).
  
• 　　The `PROGRAM_FILE` global is now available for determining the name of the running script ([#14114]).
  
• 　　The syntax `x.:sym` (e.g. `Base.:+`) is now supported, while using `x.(:sym)` or `x.(i)` for field access are deprecated in favor of `getfield` ([#15032]).
  
• 　　Function return type syntax `function f()::T` has been added ([#1090]). Values returned from a function with such a declaration will be converted to the specified type `T`.
  
• 　　Many more operators now support `.` prefixes (e.g. `.≤`) ([#17393]).  However, users are discouraged from overloading these, since they are mainly parsed in order to implement backwards compatibility with planned automatic broadcasting of dot operators in Julia 0.6 ([#16285]).  Explicitly qualified operator names like `Base.≤` should now use `Base.:≤` (prefixed by `@compat` if you need 0.4 compatibility via the `Compat` package).
  
• 　　User-extensible bounds check elimination is now possible with the new `@boundscheck` macro ([#14474]). This macro marks bounds checking code blocks, which the compiler may remove when encountered inside an `@inbounds` call.
  

　　点击完整更新日志查看更多内容
　　发行说明及下载地址：

• 　　https://github.com/JuliaLang/julia/releases/tag/v0.5.0
  
• 　　http://julialang.org/downloads/