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<div class="section" id="full-grammar-specification">
<h1><span class="section-number">10. </span>Full Grammar specification<a class="headerlink" href="#full-grammar-specification" title="Permalink to this headline">ΒΆ</a></h1>
<p>This is the full Python grammar, as it is read by the parser generator and used
to parse Python source files:</p>
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="c1"># Grammar for Python</span>
<span class="c1"># NOTE WELL: You should also follow all the steps listed at</span>
<span class="c1"># https://devguide.python.org/grammar/</span>
<span class="c1"># Start symbols for the grammar:</span>
<span class="c1"># single_input is a single interactive statement;</span>
<span class="c1"># file_input is a module or sequence of commands read from an input file;</span>
<span class="c1"># eval_input is the input for the eval() functions.</span>
<span class="c1"># NB: compound_stmt in single_input is followed by extra NEWLINE!</span>
<span class="n">single_input</span><span class="p">:</span> <span class="n">NEWLINE</span> <span class="o">|</span> <span class="n">simple_stmt</span> <span class="o">|</span> <span class="n">compound_stmt</span> <span class="n">NEWLINE</span>
<span class="n">file_input</span><span class="p">:</span> <span class="p">(</span><span class="n">NEWLINE</span> <span class="o">|</span> <span class="n">stmt</span><span class="p">)</span><span class="o">*</span> <span class="n">ENDMARKER</span>
<span class="n">eval_input</span><span class="p">:</span> <span class="n">testlist</span> <span class="n">NEWLINE</span><span class="o">*</span> <span class="n">ENDMARKER</span>
<span class="n">decorator</span><span class="p">:</span> <span class="s1">'@'</span> <span class="n">dotted_name</span> <span class="p">[</span> <span class="s1">'('</span> <span class="p">[</span><span class="n">arglist</span><span class="p">]</span> <span class="s1">')'</span> <span class="p">]</span> <span class="n">NEWLINE</span>
<span class="n">decorators</span><span class="p">:</span> <span class="n">decorator</span><span class="o">+</span>
<span class="n">decorated</span><span class="p">:</span> <span class="n">decorators</span> <span class="p">(</span><span class="n">classdef</span> <span class="o">|</span> <span class="n">funcdef</span> <span class="o">|</span> <span class="n">async_funcdef</span><span class="p">)</span>
<span class="n">async_funcdef</span><span class="p">:</span> <span class="s1">'async'</span> <span class="n">funcdef</span>
<span class="n">funcdef</span><span class="p">:</span> <span class="s1">'def'</span> <span class="n">NAME</span> <span class="n">parameters</span> <span class="p">[</span><span class="s1">'->'</span> <span class="n">test</span><span class="p">]</span> <span class="s1">':'</span> <span class="n">suite</span>
<span class="n">parameters</span><span class="p">:</span> <span class="s1">'('</span> <span class="p">[</span><span class="n">typedargslist</span><span class="p">]</span> <span class="s1">')'</span>
<span class="n">typedargslist</span><span class="p">:</span> <span class="p">(</span><span class="n">tfpdef</span> <span class="p">[</span><span class="s1">'='</span> <span class="n">test</span><span class="p">]</span> <span class="p">(</span><span class="s1">','</span> <span class="n">tfpdef</span> <span class="p">[</span><span class="s1">'='</span> <span class="n">test</span><span class="p">])</span><span class="o">*</span> <span class="p">[</span><span class="s1">','</span> <span class="p">[</span>
<span class="s1">'*'</span> <span class="p">[</span><span class="n">tfpdef</span><span class="p">]</span> <span class="p">(</span><span class="s1">','</span> <span class="n">tfpdef</span> <span class="p">[</span><span class="s1">'='</span> <span class="n">test</span><span class="p">])</span><span class="o">*</span> <span class="p">[</span><span class="s1">','</span> <span class="p">[</span><span class="s1">'**'</span> <span class="n">tfpdef</span> <span class="p">[</span><span class="s1">','</span><span class="p">]]]</span>
<span class="o">|</span> <span class="s1">'**'</span> <span class="n">tfpdef</span> <span class="p">[</span><span class="s1">','</span><span class="p">]]]</span>
<span class="o">|</span> <span class="s1">'*'</span> <span class="p">[</span><span class="n">tfpdef</span><span class="p">]</span> <span class="p">(</span><span class="s1">','</span> <span class="n">tfpdef</span> <span class="p">[</span><span class="s1">'='</span> <span class="n">test</span><span class="p">])</span><span class="o">*</span> <span class="p">[</span><span class="s1">','</span> <span class="p">[</span><span class="s1">'**'</span> <span class="n">tfpdef</span> <span class="p">[</span><span class="s1">','</span><span class="p">]]]</span>
<span class="o">|</span> <span class="s1">'**'</span> <span class="n">tfpdef</span> <span class="p">[</span><span class="s1">','</span><span class="p">])</span>
<span class="n">tfpdef</span><span class="p">:</span> <span class="n">NAME</span> <span class="p">[</span><span class="s1">':'</span> <span class="n">test</span><span class="p">]</span>
<span class="n">varargslist</span><span class="p">:</span> <span class="p">(</span><span class="n">vfpdef</span> <span class="p">[</span><span class="s1">'='</span> <span class="n">test</span><span class="p">]</span> <span class="p">(</span><span class="s1">','</span> <span class="n">vfpdef</span> <span class="p">[</span><span class="s1">'='</span> <span class="n">test</span><span class="p">])</span><span class="o">*</span> <span class="p">[</span><span class="s1">','</span> <span class="p">[</span>
<span class="s1">'*'</span> <span class="p">[</span><span class="n">vfpdef</span><span class="p">]</span> <span class="p">(</span><span class="s1">','</span> <span class="n">vfpdef</span> <span class="p">[</span><span class="s1">'='</span> <span class="n">test</span><span class="p">])</span><span class="o">*</span> <span class="p">[</span><span class="s1">','</span> <span class="p">[</span><span class="s1">'**'</span> <span class="n">vfpdef</span> <span class="p">[</span><span class="s1">','</span><span class="p">]]]</span>
<span class="o">|</span> <span class="s1">'**'</span> <span class="n">vfpdef</span> <span class="p">[</span><span class="s1">','</span><span class="p">]]]</span>
<span class="o">|</span> <span class="s1">'*'</span> <span class="p">[</span><span class="n">vfpdef</span><span class="p">]</span> <span class="p">(</span><span class="s1">','</span> <span class="n">vfpdef</span> <span class="p">[</span><span class="s1">'='</span> <span class="n">test</span><span class="p">])</span><span class="o">*</span> <span class="p">[</span><span class="s1">','</span> <span class="p">[</span><span class="s1">'**'</span> <span class="n">vfpdef</span> <span class="p">[</span><span class="s1">','</span><span class="p">]]]</span>
<span class="o">|</span> <span class="s1">'**'</span> <span class="n">vfpdef</span> <span class="p">[</span><span class="s1">','</span><span class="p">]</span>
<span class="p">)</span>
<span class="n">vfpdef</span><span class="p">:</span> <span class="n">NAME</span>
<span class="n">stmt</span><span class="p">:</span> <span class="n">simple_stmt</span> <span class="o">|</span> <span class="n">compound_stmt</span>
<span class="n">simple_stmt</span><span class="p">:</span> <span class="n">small_stmt</span> <span class="p">(</span><span class="s1">';'</span> <span class="n">small_stmt</span><span class="p">)</span><span class="o">*</span> <span class="p">[</span><span class="s1">';'</span><span class="p">]</span> <span class="n">NEWLINE</span>
<span class="n">small_stmt</span><span class="p">:</span> <span class="p">(</span><span class="n">expr_stmt</span> <span class="o">|</span> <span class="n">del_stmt</span> <span class="o">|</span> <span class="n">pass_stmt</span> <span class="o">|</span> <span class="n">flow_stmt</span> <span class="o">|</span>
<span class="n">import_stmt</span> <span class="o">|</span> <span class="n">global_stmt</span> <span class="o">|</span> <span class="n">nonlocal_stmt</span> <span class="o">|</span> <span class="n">assert_stmt</span><span class="p">)</span>
<span class="n">expr_stmt</span><span class="p">:</span> <span class="n">testlist_star_expr</span> <span class="p">(</span><span class="n">annassign</span> <span class="o">|</span> <span class="n">augassign</span> <span class="p">(</span><span class="n">yield_expr</span><span class="o">|</span><span class="n">testlist</span><span class="p">)</span> <span class="o">|</span>
<span class="p">(</span><span class="s1">'='</span> <span class="p">(</span><span class="n">yield_expr</span><span class="o">|</span><span class="n">testlist_star_expr</span><span class="p">))</span><span class="o">*</span><span class="p">)</span>
<span class="n">annassign</span><span class="p">:</span> <span class="s1">':'</span> <span class="n">test</span> <span class="p">[</span><span class="s1">'='</span> <span class="n">test</span><span class="p">]</span>
<span class="n">testlist_star_expr</span><span class="p">:</span> <span class="p">(</span><span class="n">test</span><span class="o">|</span><span class="n">star_expr</span><span class="p">)</span> <span class="p">(</span><span class="s1">','</span> <span class="p">(</span><span class="n">test</span><span class="o">|</span><span class="n">star_expr</span><span class="p">))</span><span class="o">*</span> <span class="p">[</span><span class="s1">','</span><span class="p">]</span>
<span class="n">augassign</span><span class="p">:</span> <span class="p">(</span><span class="s1">'+='</span> <span class="o">|</span> <span class="s1">'-='</span> <span class="o">|</span> <span class="s1">'*='</span> <span class="o">|</span> <span class="s1">'@='</span> <span class="o">|</span> <span class="s1">'/='</span> <span class="o">|</span> <span class="s1">'%='</span> <span class="o">|</span> <span class="s1">'&='</span> <span class="o">|</span> <span class="s1">'|='</span> <span class="o">|</span> <span class="s1">'^='</span> <span class="o">|</span>
<span class="s1">'<<='</span> <span class="o">|</span> <span class="s1">'>>='</span> <span class="o">|</span> <span class="s1">'**='</span> <span class="o">|</span> <span class="s1">'//='</span><span class="p">)</span>
<span class="c1"># For normal and annotated assignments, additional restrictions enforced by the interpreter</span>
<span class="n">del_stmt</span><span class="p">:</span> <span class="s1">'del'</span> <span class="n">exprlist</span>
<span class="n">pass_stmt</span><span class="p">:</span> <span class="s1">'pass'</span>
<span class="n">flow_stmt</span><span class="p">:</span> <span class="n">break_stmt</span> <span class="o">|</span> <span class="n">continue_stmt</span> <span class="o">|</span> <span class="n">return_stmt</span> <span class="o">|</span> <span class="n">raise_stmt</span> <span class="o">|</span> <span class="n">yield_stmt</span>
<span class="n">break_stmt</span><span class="p">:</span> <span class="s1">'break'</span>
<span class="n">continue_stmt</span><span class="p">:</span> <span class="s1">'continue'</span>
<span class="n">return_stmt</span><span class="p">:</span> <span class="s1">'return'</span> <span class="p">[</span><span class="n">testlist</span><span class="p">]</span>
<span class="n">yield_stmt</span><span class="p">:</span> <span class="n">yield_expr</span>
<span class="n">raise_stmt</span><span class="p">:</span> <span class="s1">'raise'</span> <span class="p">[</span><span class="n">test</span> <span class="p">[</span><span class="s1">'from'</span> <span class="n">test</span><span class="p">]]</span>
<span class="n">import_stmt</span><span class="p">:</span> <span class="n">import_name</span> <span class="o">|</span> <span class="n">import_from</span>
<span class="n">import_name</span><span class="p">:</span> <span class="s1">'import'</span> <span class="n">dotted_as_names</span>
<span class="c1"># note below: the ('.' | '...') is necessary because '...' is tokenized as ELLIPSIS</span>
<span class="n">import_from</span><span class="p">:</span> <span class="p">(</span><span class="s1">'from'</span> <span class="p">((</span><span class="s1">'.'</span> <span class="o">|</span> <span class="s1">'...'</span><span class="p">)</span><span class="o">*</span> <span class="n">dotted_name</span> <span class="o">|</span> <span class="p">(</span><span class="s1">'.'</span> <span class="o">|</span> <span class="s1">'...'</span><span class="p">)</span><span class="o">+</span><span class="p">)</span>
<span class="s1">'import'</span> <span class="p">(</span><span class="s1">'*'</span> <span class="o">|</span> <span class="s1">'('</span> <span class="n">import_as_names</span> <span class="s1">')'</span> <span class="o">|</span> <span class="n">import_as_names</span><span class="p">))</span>
<span class="n">import_as_name</span><span class="p">:</span> <span class="n">NAME</span> <span class="p">[</span><span class="s1">'as'</span> <span class="n">NAME</span><span class="p">]</span>
<span class="n">dotted_as_name</span><span class="p">:</span> <span class="n">dotted_name</span> <span class="p">[</span><span class="s1">'as'</span> <span class="n">NAME</span><span class="p">]</span>
<span class="n">import_as_names</span><span class="p">:</span> <span class="n">import_as_name</span> <span class="p">(</span><span class="s1">','</span> <span class="n">import_as_name</span><span class="p">)</span><span class="o">*</span> <span class="p">[</span><span class="s1">','</span><span class="p">]</span>
<span class="n">dotted_as_names</span><span class="p">:</span> <span class="n">dotted_as_name</span> <span class="p">(</span><span class="s1">','</span> <span class="n">dotted_as_name</span><span class="p">)</span><span class="o">*</span>
<span class="n">dotted_name</span><span class="p">:</span> <span class="n">NAME</span> <span class="p">(</span><span class="s1">'.'</span> <span class="n">NAME</span><span class="p">)</span><span class="o">*</span>
<span class="n">global_stmt</span><span class="p">:</span> <span class="s1">'global'</span> <span class="n">NAME</span> <span class="p">(</span><span class="s1">','</span> <span class="n">NAME</span><span class="p">)</span><span class="o">*</span>
<span class="n">nonlocal_stmt</span><span class="p">:</span> <span class="s1">'nonlocal'</span> <span class="n">NAME</span> <span class="p">(</span><span class="s1">','</span> <span class="n">NAME</span><span class="p">)</span><span class="o">*</span>
<span class="n">assert_stmt</span><span class="p">:</span> <span class="s1">'assert'</span> <span class="n">test</span> <span class="p">[</span><span class="s1">','</span> <span class="n">test</span><span class="p">]</span>
<span class="n">compound_stmt</span><span class="p">:</span> <span class="n">if_stmt</span> <span class="o">|</span> <span class="n">while_stmt</span> <span class="o">|</span> <span class="n">for_stmt</span> <span class="o">|</span> <span class="n">try_stmt</span> <span class="o">|</span> <span class="n">with_stmt</span> <span class="o">|</span> <span class="n">funcdef</span> <span class="o">|</span> <span class="n">classdef</span> <span class="o">|</span> <span class="n">decorated</span> <span class="o">|</span> <span class="n">async_stmt</span>
<span class="n">async_stmt</span><span class="p">:</span> <span class="s1">'async'</span> <span class="p">(</span><span class="n">funcdef</span> <span class="o">|</span> <span class="n">with_stmt</span> <span class="o">|</span> <span class="n">for_stmt</span><span class="p">)</span>
<span class="n">if_stmt</span><span class="p">:</span> <span class="s1">'if'</span> <span class="n">test</span> <span class="s1">':'</span> <span class="n">suite</span> <span class="p">(</span><span class="s1">'elif'</span> <span class="n">test</span> <span class="s1">':'</span> <span class="n">suite</span><span class="p">)</span><span class="o">*</span> <span class="p">[</span><span class="s1">'else'</span> <span class="s1">':'</span> <span class="n">suite</span><span class="p">]</span>
<span class="n">while_stmt</span><span class="p">:</span> <span class="s1">'while'</span> <span class="n">test</span> <span class="s1">':'</span> <span class="n">suite</span> <span class="p">[</span><span class="s1">'else'</span> <span class="s1">':'</span> <span class="n">suite</span><span class="p">]</span>
<span class="n">for_stmt</span><span class="p">:</span> <span class="s1">'for'</span> <span class="n">exprlist</span> <span class="s1">'in'</span> <span class="n">testlist</span> <span class="s1">':'</span> <span class="n">suite</span> <span class="p">[</span><span class="s1">'else'</span> <span class="s1">':'</span> <span class="n">suite</span><span class="p">]</span>
<span class="n">try_stmt</span><span class="p">:</span> <span class="p">(</span><span class="s1">'try'</span> <span class="s1">':'</span> <span class="n">suite</span>
<span class="p">((</span><span class="n">except_clause</span> <span class="s1">':'</span> <span class="n">suite</span><span class="p">)</span><span class="o">+</span>
<span class="p">[</span><span class="s1">'else'</span> <span class="s1">':'</span> <span class="n">suite</span><span class="p">]</span>
<span class="p">[</span><span class="s1">'finally'</span> <span class="s1">':'</span> <span class="n">suite</span><span class="p">]</span> <span class="o">|</span>
<span class="s1">'finally'</span> <span class="s1">':'</span> <span class="n">suite</span><span class="p">))</span>
<span class="n">with_stmt</span><span class="p">:</span> <span class="s1">'with'</span> <span class="n">with_item</span> <span class="p">(</span><span class="s1">','</span> <span class="n">with_item</span><span class="p">)</span><span class="o">*</span> <span class="s1">':'</span> <span class="n">suite</span>
<span class="n">with_item</span><span class="p">:</span> <span class="n">test</span> <span class="p">[</span><span class="s1">'as'</span> <span class="n">expr</span><span class="p">]</span>
<span class="c1"># NB compile.c makes sure that the default except clause is last</span>
<span class="n">except_clause</span><span class="p">:</span> <span class="s1">'except'</span> <span class="p">[</span><span class="n">test</span> <span class="p">[</span><span class="s1">'as'</span> <span class="n">NAME</span><span class="p">]]</span>
<span class="n">suite</span><span class="p">:</span> <span class="n">simple_stmt</span> <span class="o">|</span> <span class="n">NEWLINE</span> <span class="n">INDENT</span> <span class="n">stmt</span><span class="o">+</span> <span class="n">DEDENT</span>
<span class="n">test</span><span class="p">:</span> <span class="n">or_test</span> <span class="p">[</span><span class="s1">'if'</span> <span class="n">or_test</span> <span class="s1">'else'</span> <span class="n">test</span><span class="p">]</span> <span class="o">|</span> <span class="n">lambdef</span>
<span class="n">test_nocond</span><span class="p">:</span> <span class="n">or_test</span> <span class="o">|</span> <span class="n">lambdef_nocond</span>
<span class="n">lambdef</span><span class="p">:</span> <span class="s1">'lambda'</span> <span class="p">[</span><span class="n">varargslist</span><span class="p">]</span> <span class="s1">':'</span> <span class="n">test</span>
<span class="n">lambdef_nocond</span><span class="p">:</span> <span class="s1">'lambda'</span> <span class="p">[</span><span class="n">varargslist</span><span class="p">]</span> <span class="s1">':'</span> <span class="n">test_nocond</span>
<span class="n">or_test</span><span class="p">:</span> <span class="n">and_test</span> <span class="p">(</span><span class="s1">'or'</span> <span class="n">and_test</span><span class="p">)</span><span class="o">*</span>
<span class="n">and_test</span><span class="p">:</span> <span class="n">not_test</span> <span class="p">(</span><span class="s1">'and'</span> <span class="n">not_test</span><span class="p">)</span><span class="o">*</span>
<span class="n">not_test</span><span class="p">:</span> <span class="s1">'not'</span> <span class="n">not_test</span> <span class="o">|</span> <span class="n">comparison</span>
<span class="n">comparison</span><span class="p">:</span> <span class="n">expr</span> <span class="p">(</span><span class="n">comp_op</span> <span class="n">expr</span><span class="p">)</span><span class="o">*</span>
<span class="c1"># <> isn't actually a valid comparison operator in Python. It's here for the</span>
<span class="c1"># sake of a __future__ import described in PEP 401 (which really works :-)</span>
<span class="n">comp_op</span><span class="p">:</span> <span class="s1">'<'</span><span class="o">|</span><span class="s1">'>'</span><span class="o">|</span><span class="s1">'=='</span><span class="o">|</span><span class="s1">'>='</span><span class="o">|</span><span class="s1">'<='</span><span class="o">|</span><span class="s1">'<>'</span><span class="o">|</span><span class="s1">'!='</span><span class="o">|</span><span class="s1">'in'</span><span class="o">|</span><span class="s1">'not'</span> <span class="s1">'in'</span><span class="o">|</span><span class="s1">'is'</span><span class="o">|</span><span class="s1">'is'</span> <span class="s1">'not'</span>
<span class="n">star_expr</span><span class="p">:</span> <span class="s1">'*'</span> <span class="n">expr</span>
<span class="n">expr</span><span class="p">:</span> <span class="n">xor_expr</span> <span class="p">(</span><span class="s1">'|'</span> <span class="n">xor_expr</span><span class="p">)</span><span class="o">*</span>
<span class="n">xor_expr</span><span class="p">:</span> <span class="n">and_expr</span> <span class="p">(</span><span class="s1">'^'</span> <span class="n">and_expr</span><span class="p">)</span><span class="o">*</span>
<span class="n">and_expr</span><span class="p">:</span> <span class="n">shift_expr</span> <span class="p">(</span><span class="s1">'&'</span> <span class="n">shift_expr</span><span class="p">)</span><span class="o">*</span>
<span class="n">shift_expr</span><span class="p">:</span> <span class="n">arith_expr</span> <span class="p">((</span><span class="s1">'<<'</span><span class="o">|</span><span class="s1">'>>'</span><span class="p">)</span> <span class="n">arith_expr</span><span class="p">)</span><span class="o">*</span>
<span class="n">arith_expr</span><span class="p">:</span> <span class="n">term</span> <span class="p">((</span><span class="s1">'+'</span><span class="o">|</span><span class="s1">'-'</span><span class="p">)</span> <span class="n">term</span><span class="p">)</span><span class="o">*</span>
<span class="n">term</span><span class="p">:</span> <span class="n">factor</span> <span class="p">((</span><span class="s1">'*'</span><span class="o">|</span><span class="s1">'@'</span><span class="o">|</span><span class="s1">'/'</span><span class="o">|</span><span class="s1">'%'</span><span class="o">|</span><span class="s1">'//'</span><span class="p">)</span> <span class="n">factor</span><span class="p">)</span><span class="o">*</span>
<span class="n">factor</span><span class="p">:</span> <span class="p">(</span><span class="s1">'+'</span><span class="o">|</span><span class="s1">'-'</span><span class="o">|</span><span class="s1">'~'</span><span class="p">)</span> <span class="n">factor</span> <span class="o">|</span> <span class="n">power</span>
<span class="n">power</span><span class="p">:</span> <span class="n">atom_expr</span> <span class="p">[</span><span class="s1">'**'</span> <span class="n">factor</span><span class="p">]</span>
<span class="n">atom_expr</span><span class="p">:</span> <span class="p">[</span><span class="s1">'await'</span><span class="p">]</span> <span class="n">atom</span> <span class="n">trailer</span><span class="o">*</span>
<span class="n">atom</span><span class="p">:</span> <span class="p">(</span><span class="s1">'('</span> <span class="p">[</span><span class="n">yield_expr</span><span class="o">|</span><span class="n">testlist_comp</span><span class="p">]</span> <span class="s1">')'</span> <span class="o">|</span>
<span class="s1">'['</span> <span class="p">[</span><span class="n">testlist_comp</span><span class="p">]</span> <span class="s1">']'</span> <span class="o">|</span>
<span class="s1">'{'</span> <span class="p">[</span><span class="n">dictorsetmaker</span><span class="p">]</span> <span class="s1">'}'</span> <span class="o">|</span>
<span class="n">NAME</span> <span class="o">|</span> <span class="n">NUMBER</span> <span class="o">|</span> <span class="n">STRING</span><span class="o">+</span> <span class="o">|</span> <span class="s1">'...'</span> <span class="o">|</span> <span class="s1">'None'</span> <span class="o">|</span> <span class="s1">'True'</span> <span class="o">|</span> <span class="s1">'False'</span><span class="p">)</span>
<span class="n">testlist_comp</span><span class="p">:</span> <span class="p">(</span><span class="n">test</span><span class="o">|</span><span class="n">star_expr</span><span class="p">)</span> <span class="p">(</span> <span class="n">comp_for</span> <span class="o">|</span> <span class="p">(</span><span class="s1">','</span> <span class="p">(</span><span class="n">test</span><span class="o">|</span><span class="n">star_expr</span><span class="p">))</span><span class="o">*</span> <span class="p">[</span><span class="s1">','</span><span class="p">]</span> <span class="p">)</span>
<span class="n">trailer</span><span class="p">:</span> <span class="s1">'('</span> <span class="p">[</span><span class="n">arglist</span><span class="p">]</span> <span class="s1">')'</span> <span class="o">|</span> <span class="s1">'['</span> <span class="n">subscriptlist</span> <span class="s1">']'</span> <span class="o">|</span> <span class="s1">'.'</span> <span class="n">NAME</span>
<span class="n">subscriptlist</span><span class="p">:</span> <span class="n">subscript</span> <span class="p">(</span><span class="s1">','</span> <span class="n">subscript</span><span class="p">)</span><span class="o">*</span> <span class="p">[</span><span class="s1">','</span><span class="p">]</span>
<span class="n">subscript</span><span class="p">:</span> <span class="n">test</span> <span class="o">|</span> <span class="p">[</span><span class="n">test</span><span class="p">]</span> <span class="s1">':'</span> <span class="p">[</span><span class="n">test</span><span class="p">]</span> <span class="p">[</span><span class="n">sliceop</span><span class="p">]</span>
<span class="n">sliceop</span><span class="p">:</span> <span class="s1">':'</span> <span class="p">[</span><span class="n">test</span><span class="p">]</span>
<span class="n">exprlist</span><span class="p">:</span> <span class="p">(</span><span class="n">expr</span><span class="o">|</span><span class="n">star_expr</span><span class="p">)</span> <span class="p">(</span><span class="s1">','</span> <span class="p">(</span><span class="n">expr</span><span class="o">|</span><span class="n">star_expr</span><span class="p">))</span><span class="o">*</span> <span class="p">[</span><span class="s1">','</span><span class="p">]</span>
<span class="n">testlist</span><span class="p">:</span> <span class="n">test</span> <span class="p">(</span><span class="s1">','</span> <span class="n">test</span><span class="p">)</span><span class="o">*</span> <span class="p">[</span><span class="s1">','</span><span class="p">]</span>
<span class="n">dictorsetmaker</span><span class="p">:</span> <span class="p">(</span> <span class="p">((</span><span class="n">test</span> <span class="s1">':'</span> <span class="n">test</span> <span class="o">|</span> <span class="s1">'**'</span> <span class="n">expr</span><span class="p">)</span>
<span class="p">(</span><span class="n">comp_for</span> <span class="o">|</span> <span class="p">(</span><span class="s1">','</span> <span class="p">(</span><span class="n">test</span> <span class="s1">':'</span> <span class="n">test</span> <span class="o">|</span> <span class="s1">'**'</span> <span class="n">expr</span><span class="p">))</span><span class="o">*</span> <span class="p">[</span><span class="s1">','</span><span class="p">]))</span> <span class="o">|</span>
<span class="p">((</span><span class="n">test</span> <span class="o">|</span> <span class="n">star_expr</span><span class="p">)</span>
<span class="p">(</span><span class="n">comp_for</span> <span class="o">|</span> <span class="p">(</span><span class="s1">','</span> <span class="p">(</span><span class="n">test</span> <span class="o">|</span> <span class="n">star_expr</span><span class="p">))</span><span class="o">*</span> <span class="p">[</span><span class="s1">','</span><span class="p">]))</span> <span class="p">)</span>
<span class="n">classdef</span><span class="p">:</span> <span class="s1">'class'</span> <span class="n">NAME</span> <span class="p">[</span><span class="s1">'('</span> <span class="p">[</span><span class="n">arglist</span><span class="p">]</span> <span class="s1">')'</span><span class="p">]</span> <span class="s1">':'</span> <span class="n">suite</span>
<span class="n">arglist</span><span class="p">:</span> <span class="n">argument</span> <span class="p">(</span><span class="s1">','</span> <span class="n">argument</span><span class="p">)</span><span class="o">*</span> <span class="p">[</span><span class="s1">','</span><span class="p">]</span>
<span class="c1"># The reason that keywords are test nodes instead of NAME is that using NAME</span>
<span class="c1"># results in an ambiguity. ast.c makes sure it's a NAME.</span>
<span class="c1"># "test '=' test" is really "keyword '=' test", but we have no such token.</span>
<span class="c1"># These need to be in a single rule to avoid grammar that is ambiguous</span>
<span class="c1"># to our LL(1) parser. Even though 'test' includes '*expr' in star_expr,</span>
<span class="c1"># we explicitly match '*' here, too, to give it proper precedence.</span>
<span class="c1"># Illegal combinations and orderings are blocked in ast.c:</span>
<span class="c1"># multiple (test comp_for) arguments are blocked; keyword unpackings</span>
<span class="c1"># that precede iterable unpackings are blocked; etc.</span>
<span class="n">argument</span><span class="p">:</span> <span class="p">(</span> <span class="n">test</span> <span class="p">[</span><span class="n">comp_for</span><span class="p">]</span> <span class="o">|</span>
<span class="n">test</span> <span class="s1">'='</span> <span class="n">test</span> <span class="o">|</span>
<span class="s1">'**'</span> <span class="n">test</span> <span class="o">|</span>
<span class="s1">'*'</span> <span class="n">test</span> <span class="p">)</span>
<span class="n">comp_iter</span><span class="p">:</span> <span class="n">comp_for</span> <span class="o">|</span> <span class="n">comp_if</span>
<span class="n">sync_comp_for</span><span class="p">:</span> <span class="s1">'for'</span> <span class="n">exprlist</span> <span class="s1">'in'</span> <span class="n">or_test</span> <span class="p">[</span><span class="n">comp_iter</span><span class="p">]</span>
<span class="n">comp_for</span><span class="p">:</span> <span class="p">[</span><span class="s1">'async'</span><span class="p">]</span> <span class="n">sync_comp_for</span>
<span class="n">comp_if</span><span class="p">:</span> <span class="s1">'if'</span> <span class="n">test_nocond</span> <span class="p">[</span><span class="n">comp_iter</span><span class="p">]</span>
<span class="c1"># not used in grammar, but may appear in "node" passed from Parser to Compiler</span>
<span class="n">encoding_decl</span><span class="p">:</span> <span class="n">NAME</span>
<span class="n">yield_expr</span><span class="p">:</span> <span class="s1">'yield'</span> <span class="p">[</span><span class="n">yield_arg</span><span class="p">]</span>
<span class="n">yield_arg</span><span class="p">:</span> <span class="s1">'from'</span> <span class="n">test</span> <span class="o">|</span> <span class="n">testlist</span>
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