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<div class="section" id="full-grammar-specification">
<h1>9. 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"><div class="highlight"><pre><span class="c"># Grammar for Python</span>
<span class="c"># Note: Changing the grammar specified in this file will most likely</span>
<span class="c"># require corresponding changes in the parser module</span>
<span class="c"># (../Modules/parsermodule.c). If you can't make the changes to</span>
<span class="c"># that module yourself, please co-ordinate the required changes</span>
<span class="c"># with someone who can; ask around on python-dev for help. Fred</span>
<span class="c"># Drake <fdrake@acm.org> will probably be listening there.</span>
<span class="c"># NOTE WELL: You should also follow all the steps listed in PEP 306,</span>
<span class="c"># "How to Change Python's Grammar"</span>
<span class="c"># Start symbols for the grammar:</span>
<span class="c"># single_input is a single interactive statement;</span>
<span class="c"># file_input is a module or sequence of commands read from an input file;</span>
<span class="c"># eval_input is the input for the eval() and input() functions.</span>
<span class="c"># 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="s">'@'</span> <span class="n">dotted_name</span> <span class="p">[</span> <span class="s">'('</span> <span class="p">[</span><span class="n">arglist</span><span class="p">]</span> <span class="s">')'</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="p">)</span>
<span class="n">funcdef</span><span class="p">:</span> <span class="s">'def'</span> <span class="n">NAME</span> <span class="n">parameters</span> <span class="p">[</span><span class="s">'->'</span> <span class="n">test</span><span class="p">]</span> <span class="s">':'</span> <span class="n">suite</span>
<span class="n">parameters</span><span class="p">:</span> <span class="s">'('</span> <span class="p">[</span><span class="n">typedargslist</span><span class="p">]</span> <span class="s">')'</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="s">'='</span> <span class="n">test</span><span class="p">]</span> <span class="p">(</span><span class="s">','</span> <span class="n">tfpdef</span> <span class="p">[</span><span class="s">'='</span> <span class="n">test</span><span class="p">])</span><span class="o">*</span> <span class="p">[</span><span class="s">','</span>
<span class="p">[</span><span class="s">'*'</span> <span class="p">[</span><span class="n">tfpdef</span><span class="p">]</span> <span class="p">(</span><span class="s">','</span> <span class="n">tfpdef</span> <span class="p">[</span><span class="s">'='</span> <span class="n">test</span><span class="p">])</span><span class="o">*</span> <span class="p">[</span><span class="s">','</span> <span class="s">'**'</span> <span class="n">tfpdef</span><span class="p">]</span> <span class="o">|</span> <span class="s">'**'</span> <span class="n">tfpdef</span><span class="p">]]</span>
<span class="o">|</span> <span class="s">'*'</span> <span class="p">[</span><span class="n">tfpdef</span><span class="p">]</span> <span class="p">(</span><span class="s">','</span> <span class="n">tfpdef</span> <span class="p">[</span><span class="s">'='</span> <span class="n">test</span><span class="p">])</span><span class="o">*</span> <span class="p">[</span><span class="s">','</span> <span class="s">'**'</span> <span class="n">tfpdef</span><span class="p">]</span> <span class="o">|</span> <span class="s">'**'</span> <span class="n">tfpdef</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="s">':'</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="s">'='</span> <span class="n">test</span><span class="p">]</span> <span class="p">(</span><span class="s">','</span> <span class="n">vfpdef</span> <span class="p">[</span><span class="s">'='</span> <span class="n">test</span><span class="p">])</span><span class="o">*</span> <span class="p">[</span><span class="s">','</span>
<span class="p">[</span><span class="s">'*'</span> <span class="p">[</span><span class="n">vfpdef</span><span class="p">]</span> <span class="p">(</span><span class="s">','</span> <span class="n">vfpdef</span> <span class="p">[</span><span class="s">'='</span> <span class="n">test</span><span class="p">])</span><span class="o">*</span> <span class="p">[</span><span class="s">','</span> <span class="s">'**'</span> <span class="n">vfpdef</span><span class="p">]</span> <span class="o">|</span> <span class="s">'**'</span> <span class="n">vfpdef</span><span class="p">]]</span>
<span class="o">|</span> <span class="s">'*'</span> <span class="p">[</span><span class="n">vfpdef</span><span class="p">]</span> <span class="p">(</span><span class="s">','</span> <span class="n">vfpdef</span> <span class="p">[</span><span class="s">'='</span> <span class="n">test</span><span class="p">])</span><span class="o">*</span> <span class="p">[</span><span class="s">','</span> <span class="s">'**'</span> <span class="n">vfpdef</span><span class="p">]</span> <span class="o">|</span> <span class="s">'**'</span> <span class="n">vfpdef</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="s">';'</span> <span class="n">small_stmt</span><span class="p">)</span><span class="o">*</span> <span class="p">[</span><span class="s">';'</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">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="s">'='</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">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="s">','</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="s">','</span><span class="p">]</span>
<span class="n">augassign</span><span class="p">:</span> <span class="p">(</span><span class="s">'+='</span> <span class="o">|</span> <span class="s">'-='</span> <span class="o">|</span> <span class="s">'*='</span> <span class="o">|</span> <span class="s">'/='</span> <span class="o">|</span> <span class="s">'%='</span> <span class="o">|</span> <span class="s">'&='</span> <span class="o">|</span> <span class="s">'|='</span> <span class="o">|</span> <span class="s">'^='</span> <span class="o">|</span>
<span class="s">'<<='</span> <span class="o">|</span> <span class="s">'>>='</span> <span class="o">|</span> <span class="s">'**='</span> <span class="o">|</span> <span class="s">'//='</span><span class="p">)</span>
<span class="c"># For normal assignments, additional restrictions enforced by the interpreter</span>
<span class="n">del_stmt</span><span class="p">:</span> <span class="s">'del'</span> <span class="n">exprlist</span>
<span class="n">pass_stmt</span><span class="p">:</span> <span class="s">'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="s">'break'</span>
<span class="n">continue_stmt</span><span class="p">:</span> <span class="s">'continue'</span>
<span class="n">return_stmt</span><span class="p">:</span> <span class="s">'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="s">'raise'</span> <span class="p">[</span><span class="n">test</span> <span class="p">[</span><span class="s">'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="s">'import'</span> <span class="n">dotted_as_names</span>
<span class="c"># 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="s">'from'</span> <span class="p">((</span><span class="s">'.'</span> <span class="o">|</span> <span class="s">'...'</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="s">'.'</span> <span class="o">|</span> <span class="s">'...'</span><span class="p">)</span><span class="o">+</span><span class="p">)</span>
<span class="s">'import'</span> <span class="p">(</span><span class="s">'*'</span> <span class="o">|</span> <span class="s">'('</span> <span class="n">import_as_names</span> <span class="s">')'</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="s">'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="s">'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="s">','</span> <span class="n">import_as_name</span><span class="p">)</span><span class="o">*</span> <span class="p">[</span><span class="s">','</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="s">','</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="s">'.'</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="s">'global'</span> <span class="n">NAME</span> <span class="p">(</span><span class="s">','</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="s">'nonlocal'</span> <span class="n">NAME</span> <span class="p">(</span><span class="s">','</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="s">'assert'</span> <span class="n">test</span> <span class="p">[</span><span class="s">','</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="n">if_stmt</span><span class="p">:</span> <span class="s">'if'</span> <span class="n">test</span> <span class="s">':'</span> <span class="n">suite</span> <span class="p">(</span><span class="s">'elif'</span> <span class="n">test</span> <span class="s">':'</span> <span class="n">suite</span><span class="p">)</span><span class="o">*</span> <span class="p">[</span><span class="s">'else'</span> <span class="s">':'</span> <span class="n">suite</span><span class="p">]</span>
<span class="n">while_stmt</span><span class="p">:</span> <span class="s">'while'</span> <span class="n">test</span> <span class="s">':'</span> <span class="n">suite</span> <span class="p">[</span><span class="s">'else'</span> <span class="s">':'</span> <span class="n">suite</span><span class="p">]</span>
<span class="n">for_stmt</span><span class="p">:</span> <span class="s">'for'</span> <span class="n">exprlist</span> <span class="s">'in'</span> <span class="n">testlist</span> <span class="s">':'</span> <span class="n">suite</span> <span class="p">[</span><span class="s">'else'</span> <span class="s">':'</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="s">'try'</span> <span class="s">':'</span> <span class="n">suite</span>
<span class="p">((</span><span class="n">except_clause</span> <span class="s">':'</span> <span class="n">suite</span><span class="p">)</span><span class="o">+</span>
<span class="p">[</span><span class="s">'else'</span> <span class="s">':'</span> <span class="n">suite</span><span class="p">]</span>
<span class="p">[</span><span class="s">'finally'</span> <span class="s">':'</span> <span class="n">suite</span><span class="p">]</span> <span class="o">|</span>
<span class="s">'finally'</span> <span class="s">':'</span> <span class="n">suite</span><span class="p">))</span>
<span class="n">with_stmt</span><span class="p">:</span> <span class="s">'with'</span> <span class="n">with_item</span> <span class="p">(</span><span class="s">','</span> <span class="n">with_item</span><span class="p">)</span><span class="o">*</span> <span class="s">':'</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="s">'as'</span> <span class="n">expr</span><span class="p">]</span>
<span class="c"># 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="s">'except'</span> <span class="p">[</span><span class="n">test</span> <span class="p">[</span><span class="s">'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="s">'if'</span> <span class="n">or_test</span> <span class="s">'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="s">'lambda'</span> <span class="p">[</span><span class="n">varargslist</span><span class="p">]</span> <span class="s">':'</span> <span class="n">test</span>
<span class="n">lambdef_nocond</span><span class="p">:</span> <span class="s">'lambda'</span> <span class="p">[</span><span class="n">varargslist</span><span class="p">]</span> <span class="s">':'</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="s">'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="s">'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="s">'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="n">comp_op</span><span class="p">:</span> <span class="s">'<'</span><span class="o">|</span><span class="s">'>'</span><span class="o">|</span><span class="s">'=='</span><span class="o">|</span><span class="s">'>='</span><span class="o">|</span><span class="s">'<='</span><span class="o">|</span><span class="s">'<>'</span><span class="o">|</span><span class="s">'!='</span><span class="o">|</span><span class="s">'in'</span><span class="o">|</span><span class="s">'not'</span> <span class="s">'in'</span><span class="o">|</span><span class="s">'is'</span><span class="o">|</span><span class="s">'is'</span> <span class="s">'not'</span>
<span class="n">star_expr</span><span class="p">:</span> <span class="s">'*'</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="s">'|'</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="s">'^'</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="s">'&'</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="s">'<<'</span><span class="o">|</span><span class="s">'>>'</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="s">'+'</span><span class="o">|</span><span class="s">'-'</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="s">'*'</span><span class="o">|</span><span class="s">'/'</span><span class="o">|</span><span class="s">'%'</span><span class="o">|</span><span class="s">'//'</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="s">'+'</span><span class="o">|</span><span class="s">'-'</span><span class="o">|</span><span class="s">'~'</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</span> <span class="n">trailer</span><span class="o">*</span> <span class="p">[</span><span class="s">'**'</span> <span class="n">factor</span><span class="p">]</span>
<span class="n">atom</span><span class="p">:</span> <span class="p">(</span><span class="s">'('</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="s">')'</span> <span class="o">|</span>
<span class="s">'['</span> <span class="p">[</span><span class="n">testlist_comp</span><span class="p">]</span> <span class="s">']'</span> <span class="o">|</span>
<span class="s">'{'</span> <span class="p">[</span><span class="n">dictorsetmaker</span><span class="p">]</span> <span class="s">'}'</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="s">'...'</span> <span class="o">|</span> <span class="s">'None'</span> <span class="o">|</span> <span class="s">'True'</span> <span class="o">|</span> <span class="s">'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="s">','</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="s">','</span><span class="p">]</span> <span class="p">)</span>
<span class="n">trailer</span><span class="p">:</span> <span class="s">'('</span> <span class="p">[</span><span class="n">arglist</span><span class="p">]</span> <span class="s">')'</span> <span class="o">|</span> <span class="s">'['</span> <span class="n">subscriptlist</span> <span class="s">']'</span> <span class="o">|</span> <span class="s">'.'</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="s">','</span> <span class="n">subscript</span><span class="p">)</span><span class="o">*</span> <span class="p">[</span><span class="s">','</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="s">':'</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="s">':'</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="s">','</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="s">','</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="s">','</span> <span class="n">test</span><span class="p">)</span><span class="o">*</span> <span class="p">[</span><span class="s">','</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="s">':'</span> <span class="n">test</span> <span class="p">(</span><span class="n">comp_for</span> <span class="o">|</span> <span class="p">(</span><span class="s">','</span> <span class="n">test</span> <span class="s">':'</span> <span class="n">test</span><span class="p">)</span><span class="o">*</span> <span class="p">[</span><span class="s">','</span><span class="p">]))</span> <span class="o">|</span>
<span class="p">(</span><span class="n">test</span> <span class="p">(</span><span class="n">comp_for</span> <span class="o">|</span> <span class="p">(</span><span class="s">','</span> <span class="n">test</span><span class="p">)</span><span class="o">*</span> <span class="p">[</span><span class="s">','</span><span class="p">]))</span> <span class="p">)</span>
<span class="n">classdef</span><span class="p">:</span> <span class="s">'class'</span> <span class="n">NAME</span> <span class="p">[</span><span class="s">'('</span> <span class="p">[</span><span class="n">arglist</span><span class="p">]</span> <span class="s">')'</span><span class="p">]</span> <span class="s">':'</span> <span class="n">suite</span>
<span class="n">arglist</span><span class="p">:</span> <span class="p">(</span><span class="n">argument</span> <span class="s">','</span><span class="p">)</span><span class="o">*</span> <span class="p">(</span><span class="n">argument</span> <span class="p">[</span><span class="s">','</span><span class="p">]</span>
<span class="o">|</span><span class="s">'*'</span> <span class="n">test</span> <span class="p">(</span><span class="s">','</span> <span class="n">argument</span><span class="p">)</span><span class="o">*</span> <span class="p">[</span><span class="s">','</span> <span class="s">'**'</span> <span class="n">test</span><span class="p">]</span>
<span class="o">|</span><span class="s">'**'</span> <span class="n">test</span><span class="p">)</span>
<span class="c"># The reason that keywords are test nodes instead of NAME is that using NAME</span>
<span class="c"># results in an ambiguity. ast.c makes sure it's a NAME.</span>
<span class="n">argument</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="s">'='</span> <span class="n">test</span> <span class="c"># Really [keyword '='] test</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">comp_for</span><span class="p">:</span> <span class="s">'for'</span> <span class="n">exprlist</span> <span class="s">'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_if</span><span class="p">:</span> <span class="s">'if'</span> <span class="n">test_nocond</span> <span class="p">[</span><span class="n">comp_iter</span><span class="p">]</span>
<span class="c"># 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="s">'yield'</span> <span class="p">[</span><span class="n">testlist</span><span class="p">]</span>
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