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diff --git a/doc/add_argument.html b/doc/add_argument.html index 89026ad..083ac90 100644 --- a/doc/add_argument.html +++ b/doc/add_argument.html @@ -51,9 +51,10 @@ <h1>The add_argument() method<a class="headerlink" href="#the-add-argument-method" title="Permalink to this headline">¶</a></h1> <dl class="method"> <dt id="add_argument"> -<tt class="descname">add_argument</tt><big>(</big><span class="optional">[</span><em>action</em><span class="optional">]</span><span class="optional">[</span>, <em>nargs</em><span class="optional">]</span><span class="optional">[</span>, <em>const</em><span class="optional">]</span><span class="optional">[</span>, <em>default</em><span class="optional">]</span><span class="optional">[</span>, <em>type</em><span class="optional">]</span><span class="optional">[</span>, <em>choices</em><span class="optional">]</span><span class="optional">[</span>, <em>required</em><span class="optional">]</span><span class="optional">[</span>, <em>help</em><span class="optional">]</span><span class="optional">[</span>, <em>metavar</em><span class="optional">]</span><span class="optional">[</span>, <em>dest</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#add_argument" title="Permalink to this definition">¶</a></dt> +<tt class="descname">add_argument</tt><big>(</big><em>name or flags...</em><span class="optional">[</span>, <em>action</em><span class="optional">]</span><span class="optional">[</span>, <em>nargs</em><span class="optional">]</span><span class="optional">[</span>, <em>const</em><span class="optional">]</span><span class="optional">[</span>, <em>default</em><span class="optional">]</span><span class="optional">[</span>, <em>type</em><span class="optional">]</span><span class="optional">[</span>, <em>choices</em><span class="optional">]</span><span class="optional">[</span>, <em>required</em><span class="optional">]</span><span class="optional">[</span>, <em>help</em><span class="optional">]</span><span class="optional">[</span>, <em>metavar</em><span class="optional">]</span><span class="optional">[</span>, <em>dest</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#add_argument" title="Permalink to this definition">¶</a></dt> <dd><p>Define how a single command line argument should be parsed. Each parameter has its own more detailed description below, but in short they are:</p> <ul class="simple"> +<li><a class="reference internal" href="#name-or-flags">name or flags</a> - Either a name or a list of option strings, e.g. <tt class="docutils literal"><span class="pre">foo</span></tt> or <tt class="docutils literal"><span class="pre">-f,</span> <span class="pre">--foo</span></tt></li> <li><a class="reference internal" href="#action">action</a> - The basic type of action to be taken when this argument is encountered at the command-line.</li> <li><a class="reference internal" href="#nargs">nargs</a> - The number of command-line arguments that should be consumed.</li> <li><a class="reference internal" href="#const">const</a> - A constant value required by some <a class="reference internal" href="#action">action</a> and <a class="reference internal" href="#nargs">nargs</a> selections.</li> @@ -68,9 +69,33 @@ <p>The following sections describe how each of these are used.</p> </dd></dl> +<div class="section" id="name-or-flags"> +<h2>name or flags<a class="headerlink" href="#name-or-flags" title="Permalink to this headline">¶</a></h2> +<p>The <a title="add_argument" class="reference internal" href="#add_argument"><tt class="xref docutils literal"><span class="pre">add_argument()</span></tt></a> method needs to know whether you’re expecting an optional argument, e.g. <tt class="docutils literal"><span class="pre">-f</span></tt> or <a href="#id1"><span class="problematic" id="id2">``</span></a>–foo`, or a positional argument, e.g. a list of filenames. The first arguments passed to <a title="add_argument" class="reference internal" href="#add_argument"><tt class="xref docutils literal"><span class="pre">add_argument()</span></tt></a> must therefore be either a series of flags, or a simple argument name. For example, an optional argument could be created like:</p> +<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">add_argument</span><span class="p">(</span><span class="s">'-f'</span><span class="p">,</span> <span class="s">'--foo'</span><span class="p">)</span> +</pre></div> +</div> +<p>while a positional argument could be created like:</p> +<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">add_argument</span><span class="p">(</span><span class="s">'bar'</span><span class="p">)</span> +</pre></div> +</div> +<p>When <a title="parse_args" class="reference external" href="parse_args.html#parse_args"><tt class="xref docutils literal"><span class="pre">parse_args()</span></tt></a> is called, optional arguments will be identified by the <tt class="docutils literal"><span class="pre">-</span></tt> prefix, and the remaining arguments will be assumed to be positional:</p> +<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">parser</span> <span class="o">=</span> <span class="n">argparse</span><span class="o">.</span><span class="n">ArgumentParser</span><span class="p">(</span><span class="n">prog</span><span class="o">=</span><span class="s">'PROG'</span><span class="p">)</span> +<span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">add_argument</span><span class="p">(</span><span class="s">'-f'</span><span class="p">,</span> <span class="s">'--foo'</span><span class="p">)</span> +<span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">add_argument</span><span class="p">(</span><span class="s">'bar'</span><span class="p">)</span> +<span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">parse_args</span><span class="p">([</span><span class="s">'BAR'</span><span class="p">])</span> +<span class="go">Namespace(bar='BAR', foo=None)</span> +<span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">parse_args</span><span class="p">([</span><span class="s">'BAR'</span><span class="p">,</span> <span class="s">'--foo'</span><span class="p">,</span> <span class="s">'FOO'</span><span class="p">])</span> +<span class="go">Namespace(bar='BAR', foo='FOO')</span> +<span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">parse_args</span><span class="p">([</span><span class="s">'--foo'</span><span class="p">,</span> <span class="s">'FOO'</span><span class="p">])</span> +<span class="go">usage: PROG [-h] [-f FOO] bar</span> +<span class="go">PROG: error: too few arguments</span> +</pre></div> +</div> +</div> <div class="section" id="action"> <h2>action<a class="headerlink" href="#action" title="Permalink to this headline">¶</a></h2> -<p>ArgumentParser objects associate command-line args with actions. These actions can do just about anything with the command-line args associated with them, though most actions simply add an attribute to the object returned by <a title="parse_args" class="reference external" href="parse_args.html#parse_args"><tt class="xref docutils literal"><span class="pre">parse_args()</span></tt></a>. When you specify a new argument using the <a title="add_argument" class="reference internal" href="#add_argument"><tt class="xref docutils literal"><span class="pre">add_argument()</span></tt></a> method, you can indicate how the command-line args should be handled by specifying the <tt class="docutils literal"><span class="pre">action</span></tt> keyword argument. The supported actions are:</p> +<p><a title="ArgumentParser" class="reference external" href="ArgumentParser.html#ArgumentParser"><tt class="xref docutils literal"><span class="pre">ArgumentParser</span></tt></a> objects associate command-line args with actions. These actions can do just about anything with the command-line args associated with them, though most actions simply add an attribute to the object returned by <a title="parse_args" class="reference external" href="parse_args.html#parse_args"><tt class="xref docutils literal"><span class="pre">parse_args()</span></tt></a>. When you specify a new argument using the <a title="add_argument" class="reference internal" href="#add_argument"><tt class="xref docutils literal"><span class="pre">add_argument()</span></tt></a> method, you can indicate how the command-line args should be handled by specifying the <tt class="docutils literal"><span class="pre">action</span></tt> keyword argument. The supported actions are:</p> <ul> <li><p class="first"><tt class="docutils literal"><span class="pre">'store'</span></tt> - This just stores the argument’s value. This is the default action. For example:</p> <div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">parser</span> <span class="o">=</span> <span class="n">argparse</span><span class="o">.</span><span class="n">ArgumentParser</span><span class="p">()</span> @@ -434,6 +459,7 @@ <h3><a href="index.html">Table Of Contents</a></h3> <ul> <li><a class="reference external" href="">The add_argument() method</a><ul> +<li><a class="reference external" href="#name-or-flags">name or flags</a></li> <li><a class="reference external" href="#action">action</a></li> <li><a class="reference external" href="#nargs">nargs</a></li> <li><a class="reference external" href="#const">const</a></li> |