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Language logo"/></a><h1>The Julia Language</h1><select id="version-selector" onChange="window.location.href=this.value" style="visibility: hidden"></select><form class="search" id="search-form" action="../search.html"><input id="search-query" name="q" type="text" placeholder="Search docs"/></form><ul><li><a class="toctext" href="../index.html">Home</a></li><li><span class="toctext">Manual</span><ul><li><a class="toctext" href="../manual/introduction.html">Introduction</a></li><li><a class="toctext" href="../manual/getting-started.html">Getting Started</a></li><li><a class="toctext" href="../manual/variables.html">Variables</a></li><li><a class="toctext" href="../manual/integers-and-floating-point-numbers.html">Integers and Floating-Point Numbers</a></li><li><a class="toctext" href="../manual/mathematical-operations.html">Mathematical Operations and Elementary Functions</a></li><li><a class="toctext" href="../manual/complex-and-rational-numbers.html">Complex and Rational 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href="https://github.com/JuliaLang/julia/blob/master/doc/src/stdlib/constants.md"><span class="fa"></span> Edit on GitHub</a></nav><hr/><div id="topbar"><span>Constants</span><a class="fa fa-bars" href="#"></a></div></header><h1><a class="nav-anchor" id="lib-constants-1" href="#lib-constants-1">Constants</a></h1><section class="docstring"><div class="docstring-header"><a class="docstring-binding" id="Core.nothing" href="#Core.nothing"><code>Core.nothing</code></a> — <span class="docstring-category">Constant</span>.</div><div><pre><code class="language-none">nothing</code></pre><p>The singleton instance of type <code>Void</code>, used by convention when there is no value to return (as in a C <code>void</code> function). Can be converted to an empty <code>Nullable</code> value.</p></div><a class="source-link" target="_blank" href="https://github.com/JuliaLang/julia/blob/d55cadc350d426a95fd967121ba77494d08364c8/base/docs/basedocs.jl#L691-L696">source</a></section><section class="docstring"><div class="docstring-header"><a class="docstring-binding" id="Base.PROGRAM_FILE" href="#Base.PROGRAM_FILE"><code>Base.PROGRAM_FILE</code></a> — <span class="docstring-category">Constant</span>.</div><div><pre><code class="language-none">PROGRAM_FILE</code></pre><p>A string containing the script name passed to Julia from the command line. Note that the script name remains unchanged from within included files. Alternatively see <a href="file.html#Base.@__FILE__"><code>@__FILE__</code></a>.</p></div><a class="source-link" target="_blank" href="https://github.com/JuliaLang/julia/blob/d55cadc350d426a95fd967121ba77494d08364c8/base/initdefs.jl#L5-L11">source</a></section><section class="docstring"><div class="docstring-header"><a class="docstring-binding" id="Base.ARGS" href="#Base.ARGS"><code>Base.ARGS</code></a> — <span class="docstring-category">Constant</span>.</div><div><pre><code class="language-none">ARGS</code></pre><p>An array of the command line arguments passed to Julia, as strings.</p></div><a class="source-link" target="_blank" href="https://github.com/JuliaLang/julia/blob/d55cadc350d426a95fd967121ba77494d08364c8/base/initdefs.jl#L14-L18">source</a></section><section class="docstring"><div class="docstring-header"><a class="docstring-binding" id="Base.C_NULL" href="#Base.C_NULL"><code>Base.C_NULL</code></a> — <span class="docstring-category">Constant</span>.</div><div><pre><code class="language-none">C_NULL</code></pre><p>The C null pointer constant, sometimes used when calling external code.</p></div><a class="source-link" target="_blank" href="https://github.com/JuliaLang/julia/blob/d55cadc350d426a95fd967121ba77494d08364c8/base/pointer.jl#L13-L17">source</a></section><section class="docstring"><div class="docstring-header"><a class="docstring-binding" id="Base.VERSION" href="#Base.VERSION"><code>Base.VERSION</code></a> — <span class="docstring-category">Constant</span>.</div><div><pre><code class="language-none">VERSION</code></pre><p>A <code>VersionNumber</code> object describing which version of Julia is in use. For details see <a href="../manual/strings.html#man-version-number-literals-1">Version Number Literals</a>.</p></div><a class="source-link" target="_blank" href="https://github.com/JuliaLang/julia/blob/d55cadc350d426a95fd967121ba77494d08364c8/base/version.jl#L220-L225">source</a></section><section class="docstring"><div class="docstring-header"><a class="docstring-binding" id="Base.LOAD_PATH" href="#Base.LOAD_PATH"><code>Base.LOAD_PATH</code></a> — <span class="docstring-category">Constant</span>.</div><div><pre><code class="language-none">LOAD_PATH</code></pre><p>An array of paths as strings or custom loader objects for the <code>require</code> function and <code>using</code> and <code>import</code> statements to consider when loading code. To create a custom loader type, define the type and then add appropriate methods to the <code>Base.load_hook</code> function with the following signature:</p><pre><code class="language-none">Base.load_hook(loader::Loader, name::String, found::Any)</code></pre><p>The <code>loader</code> argument is the current value in <code>LOAD_PATH</code>, <code>name</code> is the name of the module to load, and <code>found</code> is the path of any previously found code to provide <code>name</code>. If no provider has been found earlier in <code>LOAD_PATH</code> then the value of <code>found</code> will be <code>nothing</code>. Custom loader functionality is experimental and may break or change in Julia 1.0.</p></div><a class="source-link" target="_blank" href="https://github.com/JuliaLang/julia/blob/d55cadc350d426a95fd967121ba77494d08364c8/base/initdefs.jl#L30-L46">source</a></section><section class="docstring"><div class="docstring-header"><a class="docstring-binding" id="Base.JULIA_HOME" href="#Base.JULIA_HOME"><code>Base.JULIA_HOME</code></a> — <span class="docstring-category">Constant</span>.</div><div><pre><code class="language-none">JULIA_HOME</code></pre><p>A string containing the full path to the directory containing the <code>julia</code> executable.</p></div><a class="source-link" target="_blank" href="https://github.com/JuliaLang/julia/blob/d55cadc350d426a95fd967121ba77494d08364c8/base/initdefs.jl#L71-L75">source</a></section><section class="docstring"><div class="docstring-header"><a class="docstring-binding" id="Core.ANY" href="#Core.ANY"><code>Core.ANY</code></a> — <span class="docstring-category">Constant</span>.</div><div><pre><code class="language-none">ANY</code></pre><p>Equivalent to <code>Any</code> for dispatch purposes, but signals the compiler to skip code generation specialization for that field.</p></div><a class="source-link" target="_blank" href="https://github.com/JuliaLang/julia/blob/d55cadc350d426a95fd967121ba77494d08364c8/base/docs/basedocs.jl#L699-L704">source</a></section><section class="docstring"><div class="docstring-header"><a class="docstring-binding" id="Base.Sys.CPU_CORES" href="#Base.Sys.CPU_CORES"><code>Base.Sys.CPU_CORES</code></a> — <span class="docstring-category">Constant</span>.</div><div><pre><code class="language-none">Sys.CPU_CORES</code></pre><p>The number of logical CPU cores available in the system.</p><p>See the Hwloc.jl package for extended information, including number of physical cores.</p></div><a class="source-link" target="_blank" href="https://github.com/JuliaLang/julia/blob/d55cadc350d426a95fd967121ba77494d08364c8/base/sysinfo.jl#L22-L28">source</a></section><section class="docstring"><div class="docstring-header"><a class="docstring-binding" id="Base.Sys.WORD_SIZE" href="#Base.Sys.WORD_SIZE"><code>Base.Sys.WORD_SIZE</code></a> — <span class="docstring-category">Constant</span>.</div><div><pre><code class="language-none">Sys.WORD_SIZE</code></pre><p>Standard word size on the current machine, in bits.</p></div><a class="source-link" target="_blank" href="https://github.com/JuliaLang/julia/blob/d55cadc350d426a95fd967121ba77494d08364c8/base/sysinfo.jl#L53-L57">source</a></section><section class="docstring"><div class="docstring-header"><a class="docstring-binding" id="Base.Sys.KERNEL" href="#Base.Sys.KERNEL"><code>Base.Sys.KERNEL</code></a> — <span class="docstring-category">Constant</span>.</div><div><pre><code class="language-none">Sys.KERNEL</code></pre><p>A symbol representing the name of the operating system, as returned by <code>uname</code> of the build configuration.</p></div><a class="source-link" target="_blank" href="https://github.com/JuliaLang/julia/blob/d55cadc350d426a95fd967121ba77494d08364c8/base/sysinfo.jl#L39-L43">source</a></section><section class="docstring"><div class="docstring-header"><a class="docstring-binding" id="Base.Sys.ARCH" href="#Base.Sys.ARCH"><code>Base.Sys.ARCH</code></a> — <span class="docstring-category">Constant</span>.</div><div><pre><code class="language-none">Sys.ARCH</code></pre><p>A symbol representing the architecture of the build configuration.</p></div><a class="source-link" target="_blank" href="https://github.com/JuliaLang/julia/blob/d55cadc350d426a95fd967121ba77494d08364c8/base/sysinfo.jl#L31-L35">source</a></section><section class="docstring"><div class="docstring-header"><a class="docstring-binding" id="Base.Sys.MACHINE" href="#Base.Sys.MACHINE"><code>Base.Sys.MACHINE</code></a> — <span class="docstring-category">Constant</span>.</div><div><pre><code class="language-none">Sys.MACHINE</code></pre><p>A string containing the build triple.</p></div><a class="source-link" target="_blank" href="https://github.com/JuliaLang/julia/blob/d55cadc350d426a95fd967121ba77494d08364c8/base/sysinfo.jl#L46-L50">source</a></section><p>See also:</p><ul><li><p><a href="io-network.html#Base.STDIN"><code>STDIN</code></a></p></li><li><p><a href="io-network.html#Base.STDOUT"><code>STDOUT</code></a></p></li><li><p><a href="io-network.html#Base.STDERR"><code>STDERR</code></a></p></li><li><p><a href="base.html#Base.ENV"><code>ENV</code></a></p></li><li><p><a href="io-network.html#Base.ENDIAN_BOM"><code>ENDIAN_BOM</code></a></p></li><li><p><code>Libc.MS_ASYNC</code></p></li><li><p><code>Libc.MS_INVALIDATE</code></p></li><li><p><code>Libc.MS_SYNC</code></p></li><li><p><a href="libdl.html#Base.Libdl.DL_LOAD_PATH"><code>Libdl.DL_LOAD_PATH</code></a></p></li><li><p><a href="libdl.html#Base.Libdl.RTLD_NOW"><code>Libdl.RTLD_DEEPBIND</code></a></p></li><li><p><a href="libdl.html#Base.Libdl.RTLD_NOW"><code>Libdl.RTLD_LOCAL</code></a></p></li><li><p><a href="libdl.html#Base.Libdl.RTLD_NOW"><code>Libdl.RTLD_NOLOAD</code></a></p></li><li><p><a href="libdl.html#Base.Libdl.RTLD_NOW"><code>Libdl.RTLD_LAZY</code></a></p></li><li><p><a href="libdl.html#Base.Libdl.RTLD_NOW"><code>Libdl.RTLD_NOW</code></a></p></li><li><p><a href="libdl.html#Base.Libdl.RTLD_NOW"><code>Libdl.RTLD_GLOBAL</code></a></p></li><li><p><a href="libdl.html#Base.Libdl.RTLD_NOW"><code>Libdl.RTLD_NODELETE</code></a></p></li><li><p><a href="libdl.html#Base.Libdl.RTLD_NOW"><code>Libdl.RTLD_FIRST</code></a></p></li></ul><footer><hr/><a class="previous" href="linalg.html"><span class="direction">Previous</span><span class="title">Linear Algebra</span></a><a class="next" href="file.html"><span class="direction">Next</span><span class="title">Filesystem</span></a></footer></article></body></html>
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