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<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">¶</a></h1>
<p>This is the full Python grammar, derived directly from the grammar
used to generate the CPython parser (see <a class="reference external" href="https://github.com/python/cpython/tree/3.10/Grammar/python.gram">Grammar/python.gram</a>).
The version here omits details related to code generation and
error recovery.</p>
<p>The notation is a mixture of <a class="reference external" href="https://en.wikipedia.org/wiki/Extended_Backus%E2%80%93Naur_form">EBNF</a>
and <a class="reference external" href="https://en.wikipedia.org/wiki/Parsing_expression_grammar">PEG</a>.
In particular, <code class="docutils literal notranslate"><span class="pre">&</span></code> followed by a symbol, token or parenthesized
group indicates a positive lookahead (i.e., is required to match but
not consumed), while <code class="docutils literal notranslate"><span class="pre">!</span></code> indicates a negative lookahead (i.e., is
required <em>not</em> to match). We use the <code class="docutils literal notranslate"><span class="pre">|</span></code> separator to mean PEG’s
“ordered choice” (written as <code class="docutils literal notranslate"><span class="pre">/</span></code> in traditional PEG grammars). See
<span class="target" id="index-0"></span><a class="pep reference external" href="https://www.python.org/dev/peps/pep-0617"><strong>PEP 617</strong></a> for more details on the grammar’s syntax.</p>
<div class="highlight-peg notranslate"><div class="highlight"><pre><span></span><span class="c c-Singleline"># PEG grammar for Python</span>
<span class="nf">file</span><span class="p">:</span> <span class="p">[</span><span class="nf">statements</span><span class="p">]</span> ENDMARKER
<span class="nf">interactive</span><span class="p">:</span> <span class="nf">statement_newline</span>
<span class="nf">eval</span><span class="p">:</span> <span class="nf">expressions</span> NEWLINE<span class="o">*</span> ENDMARKER
<span class="nf">func_type</span><span class="p">:</span> '(' <span class="p">[</span><span class="nf">type_expressions</span><span class="p">]</span> ')' '->' <span class="nf">expression</span> NEWLINE<span class="o">*</span> ENDMARKER
<span class="nf">fstring</span><span class="p">:</span> <span class="nf">star_expressions</span>
<span class="c c-Singleline"># type_expressions allow */** but ignore them</span>
<span class="nf">type_expressions</span><span class="p">:</span>
<span class="o">|</span> ','<span class="o">.</span><span class="nf">expression</span><span class="o">+</span> ',' '*' <span class="nf">expression</span> ',' '**' <span class="nf">expression</span>
<span class="o">|</span> ','<span class="o">.</span><span class="nf">expression</span><span class="o">+</span> ',' '*' <span class="nf">expression</span>
<span class="o">|</span> ','<span class="o">.</span><span class="nf">expression</span><span class="o">+</span> ',' '**' <span class="nf">expression</span>
<span class="o">|</span> '*' <span class="nf">expression</span> ',' '**' <span class="nf">expression</span>
<span class="o">|</span> '*' <span class="nf">expression</span>
<span class="o">|</span> '**' <span class="nf">expression</span>
<span class="o">|</span> ','<span class="o">.</span><span class="nf">expression</span><span class="o">+</span>
<span class="nf">statements</span><span class="p">:</span> <span class="nf">statement</span><span class="o">+</span>
<span class="nf">statement</span><span class="p">:</span> <span class="nf">compound_stmt</span> <span class="o">|</span> <span class="nf">simple_stmts</span>
<span class="nf">statement_newline</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">compound_stmt</span> NEWLINE
<span class="o">|</span> <span class="nf">simple_stmts</span>
<span class="o">|</span> NEWLINE
<span class="o">|</span> ENDMARKER
<span class="nf">simple_stmts</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">simple_stmt</span> !';' NEWLINE <span class="c c-Singleline"># Not needed, there for speedup</span>
<span class="o">|</span> ';'<span class="o">.</span><span class="nf">simple_stmt</span><span class="o">+</span> <span class="p">[</span>';'<span class="p">]</span> NEWLINE
<span class="c c-Singleline"># NOTE: assignment MUST precede expression, else parsing a simple assignment</span>
<span class="c c-Singleline"># will throw a SyntaxError.</span>
<span class="nf">simple_stmt</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">assignment</span>
<span class="o">|</span> <span class="nf">star_expressions</span>
<span class="o">|</span> <span class="nf">return_stmt</span>
<span class="o">|</span> <span class="nf">import_stmt</span>
<span class="o">|</span> <span class="nf">raise_stmt</span>
<span class="o">|</span> <span class="k">'pass'</span>
<span class="o">|</span> <span class="nf">del_stmt</span>
<span class="o">|</span> <span class="nf">yield_stmt</span>
<span class="o">|</span> <span class="nf">assert_stmt</span>
<span class="o">|</span> <span class="k">'break'</span>
<span class="o">|</span> <span class="k">'continue'</span>
<span class="o">|</span> <span class="nf">global_stmt</span>
<span class="o">|</span> <span class="nf">nonlocal_stmt</span>
<span class="nf">compound_stmt</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">function_def</span>
<span class="o">|</span> <span class="nf">if_stmt</span>
<span class="o">|</span> <span class="nf">class_def</span>
<span class="o">|</span> <span class="nf">with_stmt</span>
<span class="o">|</span> <span class="nf">for_stmt</span>
<span class="o">|</span> <span class="nf">try_stmt</span>
<span class="o">|</span> <span class="nf">while_stmt</span>
<span class="o">|</span> <span class="nf">match_stmt</span>
<span class="c c-Singleline"># NOTE: annotated_rhs may start with 'yield'; yield_expr must start with 'yield'</span>
<span class="nf">assignment</span><span class="p">:</span>
<span class="o">|</span> NAME ':' <span class="nf">expression</span> <span class="p">[</span>'=' <span class="nf">annotated_rhs</span> <span class="p">]</span>
<span class="o">|</span> <span class="p">(</span>'(' <span class="nf">single_target</span> ')'
<span class="o">|</span> <span class="nf">single_subscript_attribute_target</span><span class="p">)</span> ':' <span class="nf">expression</span> <span class="p">[</span>'=' <span class="nf">annotated_rhs</span> <span class="p">]</span>
<span class="o">|</span> <span class="p">(</span><span class="nf">star_targets</span> '=' <span class="p">)</span><span class="o">+</span> <span class="p">(</span><span class="nf">yield_expr</span> <span class="o">|</span> <span class="nf">star_expressions</span><span class="p">)</span> !'=' <span class="p">[</span>TYPE_COMMENT<span class="p">]</span>
<span class="o">|</span> <span class="nf">single_target</span> <span class="nf">augassign</span> ~ <span class="p">(</span><span class="nf">yield_expr</span> <span class="o">|</span> <span class="nf">star_expressions</span><span class="p">)</span>
<span class="nf">augassign</span><span class="p">:</span>
<span class="o">|</span> '+='
<span class="o">|</span> '-='
<span class="o">|</span> '*='
<span class="o">|</span> '@='
<span class="o">|</span> '/='
<span class="o">|</span> '%='
<span class="o">|</span> '&='
<span class="o">|</span> '|='
<span class="o">|</span> '^='
<span class="o">|</span> '<<='
<span class="o">|</span> '>>='
<span class="o">|</span> '**='
<span class="o">|</span> '//='
<span class="nf">global_stmt</span><span class="p">:</span> <span class="k">'global'</span> ','<span class="o">.</span>NAME<span class="o">+</span>
<span class="nf">nonlocal_stmt</span><span class="p">:</span> <span class="k">'nonlocal'</span> ','<span class="o">.</span>NAME<span class="o">+</span>
<span class="nf">yield_stmt</span><span class="p">:</span> <span class="nf">yield_expr</span>
<span class="nf">assert_stmt</span><span class="p">:</span> <span class="k">'assert'</span> <span class="nf">expression</span> <span class="p">[</span>',' <span class="nf">expression</span> <span class="p">]</span>
<span class="nf">del_stmt</span><span class="p">:</span>
<span class="o">|</span> <span class="k">'del'</span> <span class="nf">del_targets</span> &<span class="p">(</span>';' <span class="o">|</span> NEWLINE<span class="p">)</span>
<span class="nf">import_stmt</span><span class="p">:</span> <span class="nf">import_name</span> <span class="o">|</span> <span class="nf">import_from</span>
<span class="nf">import_name</span><span class="p">:</span> <span class="k">'import'</span> <span class="nf">dotted_as_names</span>
<span class="c c-Singleline"># note below: the ('.' | '...') is necessary because '...' is tokenized as ELLIPSIS</span>
<span class="nf">import_from</span><span class="p">:</span>
<span class="o">|</span> <span class="k">'from'</span> <span class="p">(</span>'.' <span class="o">|</span> '...'<span class="p">)</span><span class="o">*</span> <span class="nf">dotted_name</span> <span class="k">'import'</span> <span class="nf">import_from_targets</span>
<span class="o">|</span> <span class="k">'from'</span> <span class="p">(</span>'.' <span class="o">|</span> '...'<span class="p">)</span><span class="o">+</span> <span class="k">'import'</span> <span class="nf">import_from_targets</span>
<span class="nf">import_from_targets</span><span class="p">:</span>
<span class="o">|</span> '(' <span class="nf">import_from_as_names</span> <span class="p">[</span>','<span class="p">]</span> ')'
<span class="o">|</span> <span class="nf">import_from_as_names</span> !','
<span class="o">|</span> '*'
<span class="nf">import_from_as_names</span><span class="p">:</span>
<span class="o">|</span> ','<span class="o">.</span><span class="nf">import_from_as_name</span><span class="o">+</span>
<span class="nf">import_from_as_name</span><span class="p">:</span>
<span class="o">|</span> NAME <span class="p">[</span><span class="k">'as'</span> NAME <span class="p">]</span>
<span class="nf">dotted_as_names</span><span class="p">:</span>
<span class="o">|</span> ','<span class="o">.</span><span class="nf">dotted_as_name</span><span class="o">+</span>
<span class="nf">dotted_as_name</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">dotted_name</span> <span class="p">[</span><span class="k">'as'</span> NAME <span class="p">]</span>
<span class="nf">dotted_name</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">dotted_name</span> '.' NAME
<span class="o">|</span> NAME
<span class="nf">if_stmt</span><span class="p">:</span>
<span class="o">|</span> <span class="k">'if'</span> <span class="nf">named_expression</span> ':' <span class="nf">block</span> <span class="nf">elif_stmt</span>
<span class="o">|</span> <span class="k">'if'</span> <span class="nf">named_expression</span> ':' <span class="nf">block</span> <span class="p">[</span><span class="nf">else_block</span><span class="p">]</span>
<span class="nf">elif_stmt</span><span class="p">:</span>
<span class="o">|</span> <span class="k">'elif'</span> <span class="nf">named_expression</span> ':' <span class="nf">block</span> <span class="nf">elif_stmt</span>
<span class="o">|</span> <span class="k">'elif'</span> <span class="nf">named_expression</span> ':' <span class="nf">block</span> <span class="p">[</span><span class="nf">else_block</span><span class="p">]</span>
<span class="nf">else_block</span><span class="p">:</span>
<span class="o">|</span> <span class="k">'else'</span> ':' <span class="nf">block</span>
<span class="nf">while_stmt</span><span class="p">:</span>
<span class="o">|</span> <span class="k">'while'</span> <span class="nf">named_expression</span> ':' <span class="nf">block</span> <span class="p">[</span><span class="nf">else_block</span><span class="p">]</span>
<span class="nf">for_stmt</span><span class="p">:</span>
<span class="o">|</span> <span class="k">'for'</span> <span class="nf">star_targets</span> <span class="k">'in'</span> ~ <span class="nf">star_expressions</span> ':' <span class="p">[</span>TYPE_COMMENT<span class="p">]</span> <span class="nf">block</span> <span class="p">[</span><span class="nf">else_block</span><span class="p">]</span>
<span class="o">|</span> ASYNC <span class="k">'for'</span> <span class="nf">star_targets</span> <span class="k">'in'</span> ~ <span class="nf">star_expressions</span> ':' <span class="p">[</span>TYPE_COMMENT<span class="p">]</span> <span class="nf">block</span> <span class="p">[</span><span class="nf">else_block</span><span class="p">]</span>
<span class="nf">with_stmt</span><span class="p">:</span>
<span class="o">|</span> <span class="k">'with'</span> '(' ','<span class="o">.</span><span class="nf">with_item</span><span class="o">+</span> ','<span class="o">?</span> ')' ':' <span class="nf">block</span>
<span class="o">|</span> <span class="k">'with'</span> ','<span class="o">.</span><span class="nf">with_item</span><span class="o">+</span> ':' <span class="p">[</span>TYPE_COMMENT<span class="p">]</span> <span class="nf">block</span>
<span class="o">|</span> ASYNC <span class="k">'with'</span> '(' ','<span class="o">.</span><span class="nf">with_item</span><span class="o">+</span> ','<span class="o">?</span> ')' ':' <span class="nf">block</span>
<span class="o">|</span> ASYNC <span class="k">'with'</span> ','<span class="o">.</span><span class="nf">with_item</span><span class="o">+</span> ':' <span class="p">[</span>TYPE_COMMENT<span class="p">]</span> <span class="nf">block</span>
<span class="nf">with_item</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">expression</span> <span class="k">'as'</span> <span class="nf">star_target</span> &<span class="p">(</span>',' <span class="o">|</span> ')' <span class="o">|</span> ':'<span class="p">)</span>
<span class="o">|</span> <span class="nf">expression</span>
<span class="nf">try_stmt</span><span class="p">:</span>
<span class="o">|</span> <span class="k">'try'</span> ':' <span class="nf">block</span> <span class="nf">finally_block</span>
<span class="o">|</span> <span class="k">'try'</span> ':' <span class="nf">block</span> <span class="nf">except_block</span><span class="o">+</span> <span class="p">[</span><span class="nf">else_block</span><span class="p">]</span> <span class="p">[</span><span class="nf">finally_block</span><span class="p">]</span>
<span class="nf">except_block</span><span class="p">:</span>
<span class="o">|</span> <span class="k">'except'</span> <span class="nf">expression</span> <span class="p">[</span><span class="k">'as'</span> NAME <span class="p">]</span> ':' <span class="nf">block</span>
<span class="o">|</span> <span class="k">'except'</span> ':' <span class="nf">block</span>
<span class="nf">finally_block</span><span class="p">:</span>
<span class="o">|</span> <span class="k">'finally'</span> ':' <span class="nf">block</span>
<span class="nf">match_stmt</span><span class="p">:</span>
<span class="o">|</span> <span class="k">"match"</span> <span class="nf">subject_expr</span> ':' NEWLINE INDENT <span class="nf">case_block</span><span class="o">+</span> DEDENT
<span class="nf">subject_expr</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">star_named_expression</span> ',' <span class="nf">star_named_expressions</span><span class="o">?</span>
<span class="o">|</span> <span class="nf">named_expression</span>
<span class="nf">case_block</span><span class="p">:</span>
<span class="o">|</span> <span class="k">"case"</span> <span class="nf">patterns</span> <span class="nf">guard</span><span class="o">?</span> ':' <span class="nf">block</span>
<span class="nf">guard</span><span class="p">:</span> <span class="k">'if'</span> <span class="nf">named_expression</span>
<span class="nf">patterns</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">open_sequence_pattern</span>
<span class="o">|</span> <span class="nf">pattern</span>
<span class="nf">pattern</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">as_pattern</span>
<span class="o">|</span> <span class="nf">or_pattern</span>
<span class="nf">as_pattern</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">or_pattern</span> <span class="k">'as'</span> <span class="nf">pattern_capture_target</span>
<span class="nf">or_pattern</span><span class="p">:</span>
<span class="o">|</span> '|'<span class="o">.</span><span class="nf">closed_pattern</span><span class="o">+</span>
<span class="nf">closed_pattern</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">literal_pattern</span>
<span class="o">|</span> <span class="nf">capture_pattern</span>
<span class="o">|</span> <span class="nf">wildcard_pattern</span>
<span class="o">|</span> <span class="nf">value_pattern</span>
<span class="o">|</span> <span class="nf">group_pattern</span>
<span class="o">|</span> <span class="nf">sequence_pattern</span>
<span class="o">|</span> <span class="nf">mapping_pattern</span>
<span class="o">|</span> <span class="nf">class_pattern</span>
<span class="c c-Singleline"># Literal patterns are used for equality and identity constraints</span>
<span class="nf">literal_pattern</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">signed_number</span> !<span class="p">(</span>'+' <span class="o">|</span> '-'<span class="p">)</span>
<span class="o">|</span> <span class="nf">complex_number</span>
<span class="o">|</span> <span class="nf">strings</span>
<span class="o">|</span> <span class="k">'None'</span>
<span class="o">|</span> <span class="k">'True'</span>
<span class="o">|</span> <span class="k">'False'</span>
<span class="c c-Singleline"># Literal expressions are used to restrict permitted mapping pattern keys</span>
<span class="nf">literal_expr</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">signed_number</span> !<span class="p">(</span>'+' <span class="o">|</span> '-'<span class="p">)</span>
<span class="o">|</span> <span class="nf">complex_number</span>
<span class="o">|</span> <span class="nf">strings</span>
<span class="o">|</span> <span class="k">'None'</span>
<span class="o">|</span> <span class="k">'True'</span>
<span class="o">|</span> <span class="k">'False'</span>
<span class="nf">complex_number</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">signed_real_number</span> '+' <span class="nf">imaginary_number</span>
<span class="o">|</span> <span class="nf">signed_real_number</span> '-' <span class="nf">imaginary_number</span>
<span class="nf">signed_number</span><span class="p">:</span>
<span class="o">|</span> NUMBER
<span class="o">|</span> '-' NUMBER
<span class="nf">signed_real_number</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">real_number</span>
<span class="o">|</span> '-' <span class="nf">real_number</span>
<span class="nf">real_number</span><span class="p">:</span>
<span class="o">|</span> NUMBER
<span class="nf">imaginary_number</span><span class="p">:</span>
<span class="o">|</span> NUMBER
<span class="nf">capture_pattern</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">pattern_capture_target</span>
<span class="nf">pattern_capture_target</span><span class="p">:</span>
<span class="o">|</span> !<span class="k">"_"</span> NAME !<span class="p">(</span>'.' <span class="o">|</span> '(' <span class="o">|</span> '='<span class="p">)</span>
<span class="nf">wildcard_pattern</span><span class="p">:</span>
<span class="o">|</span> <span class="k">"_"</span>
<span class="nf">value_pattern</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">attr</span> !<span class="p">(</span>'.' <span class="o">|</span> '(' <span class="o">|</span> '='<span class="p">)</span>
<span class="nf">attr</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">name_or_attr</span> '.' NAME
<span class="nf">name_or_attr</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">attr</span>
<span class="o">|</span> NAME
<span class="nf">group_pattern</span><span class="p">:</span>
<span class="o">|</span> '(' <span class="nf">pattern</span> ')'
<span class="nf">sequence_pattern</span><span class="p">:</span>
<span class="o">|</span> '[' <span class="nf">maybe_sequence_pattern</span><span class="o">?</span> ']'
<span class="o">|</span> '(' <span class="nf">open_sequence_pattern</span><span class="o">?</span> ')'
<span class="nf">open_sequence_pattern</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">maybe_star_pattern</span> ',' <span class="nf">maybe_sequence_pattern</span><span class="o">?</span>
<span class="nf">maybe_sequence_pattern</span><span class="p">:</span>
<span class="o">|</span> ','<span class="o">.</span><span class="nf">maybe_star_pattern</span><span class="o">+</span> ','<span class="o">?</span>
<span class="nf">maybe_star_pattern</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">star_pattern</span>
<span class="o">|</span> <span class="nf">pattern</span>
<span class="nf">star_pattern</span><span class="p">:</span>
<span class="o">|</span> '*' <span class="nf">pattern_capture_target</span>
<span class="o">|</span> '*' <span class="nf">wildcard_pattern</span>
<span class="nf">mapping_pattern</span><span class="p">:</span>
<span class="o">|</span> '{' '}'
<span class="o">|</span> '{' <span class="nf">double_star_pattern</span> ','<span class="o">?</span> '}'
<span class="o">|</span> '{' <span class="nf">items_pattern</span> ',' <span class="nf">double_star_pattern</span> ','<span class="o">?</span> '}'
<span class="o">|</span> '{' <span class="nf">items_pattern</span> ','<span class="o">?</span> '}'
<span class="nf">items_pattern</span><span class="p">:</span>
<span class="o">|</span> ','<span class="o">.</span><span class="nf">key_value_pattern</span><span class="o">+</span>
<span class="nf">key_value_pattern</span><span class="p">:</span>
<span class="o">|</span> <span class="p">(</span><span class="nf">literal_expr</span> <span class="o">|</span> <span class="nf">attr</span><span class="p">)</span> ':' <span class="nf">pattern</span>
<span class="nf">double_star_pattern</span><span class="p">:</span>
<span class="o">|</span> '**' <span class="nf">pattern_capture_target</span>
<span class="nf">class_pattern</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">name_or_attr</span> '(' ')'
<span class="o">|</span> <span class="nf">name_or_attr</span> '(' <span class="nf">positional_patterns</span> ','<span class="o">?</span> ')'
<span class="o">|</span> <span class="nf">name_or_attr</span> '(' <span class="nf">keyword_patterns</span> ','<span class="o">?</span> ')'
<span class="o">|</span> <span class="nf">name_or_attr</span> '(' <span class="nf">positional_patterns</span> ',' <span class="nf">keyword_patterns</span> ','<span class="o">?</span> ')'
<span class="nf">positional_patterns</span><span class="p">:</span>
<span class="o">|</span> ','<span class="o">.</span><span class="nf">pattern</span><span class="o">+</span>
<span class="nf">keyword_patterns</span><span class="p">:</span>
<span class="o">|</span> ','<span class="o">.</span><span class="nf">keyword_pattern</span><span class="o">+</span>
<span class="nf">keyword_pattern</span><span class="p">:</span>
<span class="o">|</span> NAME '=' <span class="nf">pattern</span>
<span class="nf">return_stmt</span><span class="p">:</span>
<span class="o">|</span> <span class="k">'return'</span> <span class="p">[</span><span class="nf">star_expressions</span><span class="p">]</span>
<span class="nf">raise_stmt</span><span class="p">:</span>
<span class="o">|</span> <span class="k">'raise'</span> <span class="nf">expression</span> <span class="p">[</span><span class="k">'from'</span> <span class="nf">expression</span> <span class="p">]</span>
<span class="o">|</span> <span class="k">'raise'</span>
<span class="nf">function_def</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">decorators</span> <span class="nf">function_def_raw</span>
<span class="o">|</span> <span class="nf">function_def_raw</span>
<span class="nf">function_def_raw</span><span class="p">:</span>
<span class="o">|</span> <span class="k">'def'</span> NAME '(' <span class="p">[</span><span class="nf">params</span><span class="p">]</span> ')' <span class="p">[</span>'->' <span class="nf">expression</span> <span class="p">]</span> ':' <span class="p">[</span><span class="nf">func_type_comment</span><span class="p">]</span> <span class="nf">block</span>
<span class="o">|</span> ASYNC <span class="k">'def'</span> NAME '(' <span class="p">[</span><span class="nf">params</span><span class="p">]</span> ')' <span class="p">[</span>'->' <span class="nf">expression</span> <span class="p">]</span> ':' <span class="p">[</span><span class="nf">func_type_comment</span><span class="p">]</span> <span class="nf">block</span>
<span class="nf">func_type_comment</span><span class="p">:</span>
<span class="o">|</span> NEWLINE TYPE_COMMENT &<span class="p">(</span>NEWLINE INDENT<span class="p">)</span> <span class="c c-Singleline"># Must be followed by indented block</span>
<span class="o">|</span> TYPE_COMMENT
<span class="nf">params</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">parameters</span>
<span class="nf">parameters</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">slash_no_default</span> <span class="nf">param_no_default</span><span class="o">*</span> <span class="nf">param_with_default</span><span class="o">*</span> <span class="p">[</span><span class="nf">star_etc</span><span class="p">]</span>
<span class="o">|</span> <span class="nf">slash_with_default</span> <span class="nf">param_with_default</span><span class="o">*</span> <span class="p">[</span><span class="nf">star_etc</span><span class="p">]</span>
<span class="o">|</span> <span class="nf">param_no_default</span><span class="o">+</span> <span class="nf">param_with_default</span><span class="o">*</span> <span class="p">[</span><span class="nf">star_etc</span><span class="p">]</span>
<span class="o">|</span> <span class="nf">param_with_default</span><span class="o">+</span> <span class="p">[</span><span class="nf">star_etc</span><span class="p">]</span>
<span class="o">|</span> <span class="nf">star_etc</span>
<span class="c c-Singleline"># Some duplication here because we can't write (',' | &')'),</span>
<span class="c c-Singleline"># which is because we don't support empty alternatives (yet).</span>
<span class="c c-Singleline">#</span>
<span class="nf">slash_no_default</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">param_no_default</span><span class="o">+</span> '/' ','
<span class="o">|</span> <span class="nf">param_no_default</span><span class="o">+</span> '/' &')'
<span class="nf">slash_with_default</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">param_no_default</span><span class="o">*</span> <span class="nf">param_with_default</span><span class="o">+</span> '/' ','
<span class="o">|</span> <span class="nf">param_no_default</span><span class="o">*</span> <span class="nf">param_with_default</span><span class="o">+</span> '/' &')'
<span class="nf">star_etc</span><span class="p">:</span>
<span class="o">|</span> '*' <span class="nf">param_no_default</span> <span class="nf">param_maybe_default</span><span class="o">*</span> <span class="p">[</span><span class="nf">kwds</span><span class="p">]</span>
<span class="o">|</span> '*' ',' <span class="nf">param_maybe_default</span><span class="o">+</span> <span class="p">[</span><span class="nf">kwds</span><span class="p">]</span>
<span class="o">|</span> <span class="nf">kwds</span>
<span class="nf">kwds</span><span class="p">:</span> '**' <span class="nf">param_no_default</span>
<span class="c c-Singleline"># One parameter. This *includes* a following comma and type comment.</span>
<span class="c c-Singleline">#</span>
<span class="c c-Singleline"># There are three styles:</span>
<span class="c c-Singleline"># - No default</span>
<span class="c c-Singleline"># - With default</span>
<span class="c c-Singleline"># - Maybe with default</span>
<span class="c c-Singleline">#</span>
<span class="c c-Singleline"># There are two alternative forms of each, to deal with type comments:</span>
<span class="c c-Singleline"># - Ends in a comma followed by an optional type comment</span>
<span class="c c-Singleline"># - No comma, optional type comment, must be followed by close paren</span>
<span class="c c-Singleline"># The latter form is for a final parameter without trailing comma.</span>
<span class="c c-Singleline">#</span>
<span class="nf">param_no_default</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">param</span> ',' TYPE_COMMENT<span class="o">?</span>
<span class="o">|</span> <span class="nf">param</span> TYPE_COMMENT<span class="o">?</span> &')'
<span class="nf">param_with_default</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">param</span> <span class="nf">default</span> ',' TYPE_COMMENT<span class="o">?</span>
<span class="o">|</span> <span class="nf">param</span> <span class="nf">default</span> TYPE_COMMENT<span class="o">?</span> &')'
<span class="nf">param_maybe_default</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">param</span> <span class="nf">default</span><span class="o">?</span> ',' TYPE_COMMENT<span class="o">?</span>
<span class="o">|</span> <span class="nf">param</span> <span class="nf">default</span><span class="o">?</span> TYPE_COMMENT<span class="o">?</span> &')'
<span class="nf">param</span><span class="p">:</span> NAME <span class="nf">annotation</span><span class="o">?</span>
<span class="nf">annotation</span><span class="p">:</span> ':' <span class="nf">expression</span>
<span class="nf">default</span><span class="p">:</span> '=' <span class="nf">expression</span>
<span class="nf">decorators</span><span class="p">:</span> <span class="p">(</span>'@' <span class="nf">named_expression</span> NEWLINE <span class="p">)</span><span class="o">+</span>
<span class="nf">class_def</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">decorators</span> <span class="nf">class_def_raw</span>
<span class="o">|</span> <span class="nf">class_def_raw</span>
<span class="nf">class_def_raw</span><span class="p">:</span>
<span class="o">|</span> <span class="k">'class'</span> NAME <span class="p">[</span>'(' <span class="p">[</span><span class="nf">arguments</span><span class="p">]</span> ')' <span class="p">]</span> ':' <span class="nf">block</span>
<span class="nf">block</span><span class="p">:</span>
<span class="o">|</span> NEWLINE INDENT <span class="nf">statements</span> DEDENT
<span class="o">|</span> <span class="nf">simple_stmts</span>
<span class="nf">star_expressions</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">star_expression</span> <span class="p">(</span>',' <span class="nf">star_expression</span> <span class="p">)</span><span class="o">+</span> <span class="p">[</span>','<span class="p">]</span>
<span class="o">|</span> <span class="nf">star_expression</span> ','
<span class="o">|</span> <span class="nf">star_expression</span>
<span class="nf">star_expression</span><span class="p">:</span>
<span class="o">|</span> '*' <span class="nf">bitwise_or</span>
<span class="o">|</span> <span class="nf">expression</span>
<span class="nf">star_named_expressions</span><span class="p">:</span> ','<span class="o">.</span><span class="nf">star_named_expression</span><span class="o">+</span> <span class="p">[</span>','<span class="p">]</span>
<span class="nf">star_named_expression</span><span class="p">:</span>
<span class="o">|</span> '*' <span class="nf">bitwise_or</span>
<span class="o">|</span> <span class="nf">named_expression</span>
<span class="nf">assignment_expression</span><span class="p">:</span>
<span class="o">|</span> NAME ':=' ~ <span class="nf">expression</span>
<span class="nf">named_expression</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">assignment_expression</span>
<span class="o">|</span> <span class="nf">expression</span> !':='
<span class="nf">annotated_rhs</span><span class="p">:</span> <span class="nf">yield_expr</span> <span class="o">|</span> <span class="nf">star_expressions</span>
<span class="nf">expressions</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">expression</span> <span class="p">(</span>',' <span class="nf">expression</span> <span class="p">)</span><span class="o">+</span> <span class="p">[</span>','<span class="p">]</span>
<span class="o">|</span> <span class="nf">expression</span> ','
<span class="o">|</span> <span class="nf">expression</span>
<span class="nf">expression</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">disjunction</span> <span class="k">'if'</span> <span class="nf">disjunction</span> <span class="k">'else'</span> <span class="nf">expression</span>
<span class="o">|</span> <span class="nf">disjunction</span>
<span class="o">|</span> <span class="nf">lambdef</span>
<span class="nf">lambdef</span><span class="p">:</span>
<span class="o">|</span> <span class="k">'lambda'</span> <span class="p">[</span><span class="nf">lambda_params</span><span class="p">]</span> ':' <span class="nf">expression</span>
<span class="nf">lambda_params</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">lambda_parameters</span>
<span class="c c-Singleline"># lambda_parameters etc. duplicates parameters but without annotations</span>
<span class="c c-Singleline"># or type comments, and if there's no comma after a parameter, we expect</span>
<span class="c c-Singleline"># a colon, not a close parenthesis. (For more, see parameters above.)</span>
<span class="c c-Singleline">#</span>
<span class="nf">lambda_parameters</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">lambda_slash_no_default</span> <span class="nf">lambda_param_no_default</span><span class="o">*</span> <span class="nf">lambda_param_with_default</span><span class="o">*</span> <span class="p">[</span><span class="nf">lambda_star_etc</span><span class="p">]</span>
<span class="o">|</span> <span class="nf">lambda_slash_with_default</span> <span class="nf">lambda_param_with_default</span><span class="o">*</span> <span class="p">[</span><span class="nf">lambda_star_etc</span><span class="p">]</span>
<span class="o">|</span> <span class="nf">lambda_param_no_default</span><span class="o">+</span> <span class="nf">lambda_param_with_default</span><span class="o">*</span> <span class="p">[</span><span class="nf">lambda_star_etc</span><span class="p">]</span>
<span class="o">|</span> <span class="nf">lambda_param_with_default</span><span class="o">+</span> <span class="p">[</span><span class="nf">lambda_star_etc</span><span class="p">]</span>
<span class="o">|</span> <span class="nf">lambda_star_etc</span>
<span class="nf">lambda_slash_no_default</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">lambda_param_no_default</span><span class="o">+</span> '/' ','
<span class="o">|</span> <span class="nf">lambda_param_no_default</span><span class="o">+</span> '/' &':'
<span class="nf">lambda_slash_with_default</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">lambda_param_no_default</span><span class="o">*</span> <span class="nf">lambda_param_with_default</span><span class="o">+</span> '/' ','
<span class="o">|</span> <span class="nf">lambda_param_no_default</span><span class="o">*</span> <span class="nf">lambda_param_with_default</span><span class="o">+</span> '/' &':'
<span class="nf">lambda_star_etc</span><span class="p">:</span>
<span class="o">|</span> '*' <span class="nf">lambda_param_no_default</span> <span class="nf">lambda_param_maybe_default</span><span class="o">*</span> <span class="p">[</span><span class="nf">lambda_kwds</span><span class="p">]</span>
<span class="o">|</span> '*' ',' <span class="nf">lambda_param_maybe_default</span><span class="o">+</span> <span class="p">[</span><span class="nf">lambda_kwds</span><span class="p">]</span>
<span class="o">|</span> <span class="nf">lambda_kwds</span>
<span class="nf">lambda_kwds</span><span class="p">:</span> '**' <span class="nf">lambda_param_no_default</span>
<span class="nf">lambda_param_no_default</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">lambda_param</span> ','
<span class="o">|</span> <span class="nf">lambda_param</span> &':'
<span class="nf">lambda_param_with_default</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">lambda_param</span> <span class="nf">default</span> ','
<span class="o">|</span> <span class="nf">lambda_param</span> <span class="nf">default</span> &':'
<span class="nf">lambda_param_maybe_default</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">lambda_param</span> <span class="nf">default</span><span class="o">?</span> ','
<span class="o">|</span> <span class="nf">lambda_param</span> <span class="nf">default</span><span class="o">?</span> &':'
<span class="nf">lambda_param</span><span class="p">:</span> NAME
<span class="nf">disjunction</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">conjunction</span> <span class="p">(</span><span class="k">'or'</span> <span class="nf">conjunction</span> <span class="p">)</span><span class="o">+</span>
<span class="o">|</span> <span class="nf">conjunction</span>
<span class="nf">conjunction</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">inversion</span> <span class="p">(</span><span class="k">'and'</span> <span class="nf">inversion</span> <span class="p">)</span><span class="o">+</span>
<span class="o">|</span> <span class="nf">inversion</span>
<span class="nf">inversion</span><span class="p">:</span>
<span class="o">|</span> <span class="k">'not'</span> <span class="nf">inversion</span>
<span class="o">|</span> <span class="nf">comparison</span>
<span class="nf">comparison</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">bitwise_or</span> <span class="nf">compare_op_bitwise_or_pair</span><span class="o">+</span>
<span class="o">|</span> <span class="nf">bitwise_or</span>
<span class="nf">compare_op_bitwise_or_pair</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">eq_bitwise_or</span>
<span class="o">|</span> <span class="nf">noteq_bitwise_or</span>
<span class="o">|</span> <span class="nf">lte_bitwise_or</span>
<span class="o">|</span> <span class="nf">lt_bitwise_or</span>
<span class="o">|</span> <span class="nf">gte_bitwise_or</span>
<span class="o">|</span> <span class="nf">gt_bitwise_or</span>
<span class="o">|</span> <span class="nf">notin_bitwise_or</span>
<span class="o">|</span> <span class="nf">in_bitwise_or</span>
<span class="o">|</span> <span class="nf">isnot_bitwise_or</span>
<span class="o">|</span> <span class="nf">is_bitwise_or</span>
<span class="nf">eq_bitwise_or</span><span class="p">:</span> '==' <span class="nf">bitwise_or</span>
<span class="nf">noteq_bitwise_or</span><span class="p">:</span>
<span class="o">|</span> <span class="p">(</span>'!=' <span class="p">)</span> <span class="nf">bitwise_or</span>
<span class="nf">lte_bitwise_or</span><span class="p">:</span> '<=' <span class="nf">bitwise_or</span>
<span class="nf">lt_bitwise_or</span><span class="p">:</span> '<' <span class="nf">bitwise_or</span>
<span class="nf">gte_bitwise_or</span><span class="p">:</span> '>=' <span class="nf">bitwise_or</span>
<span class="nf">gt_bitwise_or</span><span class="p">:</span> '>' <span class="nf">bitwise_or</span>
<span class="nf">notin_bitwise_or</span><span class="p">:</span> <span class="k">'not'</span> <span class="k">'in'</span> <span class="nf">bitwise_or</span>
<span class="nf">in_bitwise_or</span><span class="p">:</span> <span class="k">'in'</span> <span class="nf">bitwise_or</span>
<span class="nf">isnot_bitwise_or</span><span class="p">:</span> <span class="k">'is'</span> <span class="k">'not'</span> <span class="nf">bitwise_or</span>
<span class="nf">is_bitwise_or</span><span class="p">:</span> <span class="k">'is'</span> <span class="nf">bitwise_or</span>
<span class="nf">bitwise_or</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">bitwise_or</span> '|' <span class="nf">bitwise_xor</span>
<span class="o">|</span> <span class="nf">bitwise_xor</span>
<span class="nf">bitwise_xor</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">bitwise_xor</span> '^' <span class="nf">bitwise_and</span>
<span class="o">|</span> <span class="nf">bitwise_and</span>
<span class="nf">bitwise_and</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">bitwise_and</span> '&' <span class="nf">shift_expr</span>
<span class="o">|</span> <span class="nf">shift_expr</span>
<span class="nf">shift_expr</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">shift_expr</span> '<<' <span class="nf">sum</span>
<span class="o">|</span> <span class="nf">shift_expr</span> '>>' <span class="nf">sum</span>
<span class="o">|</span> <span class="nf">sum</span>
<span class="nf">sum</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">sum</span> '+' <span class="nf">term</span>
<span class="o">|</span> <span class="nf">sum</span> '-' <span class="nf">term</span>
<span class="o">|</span> <span class="nf">term</span>
<span class="nf">term</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">term</span> '*' <span class="nf">factor</span>
<span class="o">|</span> <span class="nf">term</span> '/' <span class="nf">factor</span>
<span class="o">|</span> <span class="nf">term</span> '//' <span class="nf">factor</span>
<span class="o">|</span> <span class="nf">term</span> '%' <span class="nf">factor</span>
<span class="o">|</span> <span class="nf">term</span> '@' <span class="nf">factor</span>
<span class="o">|</span> <span class="nf">factor</span>
<span class="nf">factor</span><span class="p">:</span>
<span class="o">|</span> '+' <span class="nf">factor</span>
<span class="o">|</span> '-' <span class="nf">factor</span>
<span class="o">|</span> '~' <span class="nf">factor</span>
<span class="o">|</span> <span class="nf">power</span>
<span class="nf">power</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">await_primary</span> '**' <span class="nf">factor</span>
<span class="o">|</span> <span class="nf">await_primary</span>
<span class="nf">await_primary</span><span class="p">:</span>
<span class="o">|</span> AWAIT <span class="nf">primary</span>
<span class="o">|</span> <span class="nf">primary</span>
<span class="nf">primary</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">primary</span> '.' NAME
<span class="o">|</span> <span class="nf">primary</span> <span class="nf">genexp</span>
<span class="o">|</span> <span class="nf">primary</span> '(' <span class="p">[</span><span class="nf">arguments</span><span class="p">]</span> ')'
<span class="o">|</span> <span class="nf">primary</span> '[' <span class="nf">slices</span> ']'
<span class="o">|</span> <span class="nf">atom</span>
<span class="nf">slices</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">slice</span> !','
<span class="o">|</span> ','<span class="o">.</span><span class="nf">slice</span><span class="o">+</span> <span class="p">[</span>','<span class="p">]</span>
<span class="nf">slice</span><span class="p">:</span>
<span class="o">|</span> <span class="p">[</span><span class="nf">expression</span><span class="p">]</span> ':' <span class="p">[</span><span class="nf">expression</span><span class="p">]</span> <span class="p">[</span>':' <span class="p">[</span><span class="nf">expression</span><span class="p">]</span> <span class="p">]</span>
<span class="o">|</span> <span class="nf">named_expression</span>
<span class="nf">atom</span><span class="p">:</span>
<span class="o">|</span> NAME
<span class="o">|</span> <span class="k">'True'</span>
<span class="o">|</span> <span class="k">'False'</span>
<span class="o">|</span> <span class="k">'None'</span>
<span class="o">|</span> <span class="nf">strings</span>
<span class="o">|</span> NUMBER
<span class="o">|</span> <span class="p">(</span><span class="nf">tuple</span> <span class="o">|</span> <span class="nf">group</span> <span class="o">|</span> <span class="nf">genexp</span><span class="p">)</span>
<span class="o">|</span> <span class="p">(</span><span class="nf">list</span> <span class="o">|</span> <span class="nf">listcomp</span><span class="p">)</span>
<span class="o">|</span> <span class="p">(</span><span class="nf">dict</span> <span class="o">|</span> <span class="nf">set</span> <span class="o">|</span> <span class="nf">dictcomp</span> <span class="o">|</span> <span class="nf">setcomp</span><span class="p">)</span>
<span class="o">|</span> '...'
<span class="nf">strings</span><span class="p">:</span> STRING<span class="o">+</span>
<span class="nf">list</span><span class="p">:</span>
<span class="o">|</span> '[' <span class="p">[</span><span class="nf">star_named_expressions</span><span class="p">]</span> ']'
<span class="nf">listcomp</span><span class="p">:</span>
<span class="o">|</span> '[' <span class="nf">named_expression</span> <span class="nf">for_if_clauses</span> ']'
<span class="nf">tuple</span><span class="p">:</span>
<span class="o">|</span> '(' <span class="p">[</span><span class="nf">star_named_expression</span> ',' <span class="p">[</span><span class="nf">star_named_expressions</span><span class="p">]</span> <span class="p">]</span> ')'
<span class="nf">group</span><span class="p">:</span>
<span class="o">|</span> '(' <span class="p">(</span><span class="nf">yield_expr</span> <span class="o">|</span> <span class="nf">named_expression</span><span class="p">)</span> ')'
<span class="nf">genexp</span><span class="p">:</span>
<span class="o">|</span> '(' <span class="p">(</span> <span class="nf">assignment_expression</span> <span class="o">|</span> <span class="nf">expression</span> !':='<span class="p">)</span> <span class="nf">for_if_clauses</span> ')'
<span class="nf">set</span><span class="p">:</span> '{' <span class="nf">star_named_expressions</span> '}'
<span class="nf">setcomp</span><span class="p">:</span>
<span class="o">|</span> '{' <span class="nf">named_expression</span> <span class="nf">for_if_clauses</span> '}'
<span class="nf">dict</span><span class="p">:</span>
<span class="o">|</span> '{' <span class="p">[</span><span class="nf">double_starred_kvpairs</span><span class="p">]</span> '}'
<span class="nf">dictcomp</span><span class="p">:</span>
<span class="o">|</span> '{' <span class="nf">kvpair</span> <span class="nf">for_if_clauses</span> '}'
<span class="nf">double_starred_kvpairs</span><span class="p">:</span> ','<span class="o">.</span><span class="nf">double_starred_kvpair</span><span class="o">+</span> <span class="p">[</span>','<span class="p">]</span>
<span class="nf">double_starred_kvpair</span><span class="p">:</span>
<span class="o">|</span> '**' <span class="nf">bitwise_or</span>
<span class="o">|</span> <span class="nf">kvpair</span>
<span class="nf">kvpair</span><span class="p">:</span> <span class="nf">expression</span> ':' <span class="nf">expression</span>
<span class="nf">for_if_clauses</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">for_if_clause</span><span class="o">+</span>
<span class="nf">for_if_clause</span><span class="p">:</span>
<span class="o">|</span> ASYNC <span class="k">'for'</span> <span class="nf">star_targets</span> <span class="k">'in'</span> ~ <span class="nf">disjunction</span> <span class="p">(</span><span class="k">'if'</span> <span class="nf">disjunction</span> <span class="p">)</span><span class="o">*</span>
<span class="o">|</span> <span class="k">'for'</span> <span class="nf">star_targets</span> <span class="k">'in'</span> ~ <span class="nf">disjunction</span> <span class="p">(</span><span class="k">'if'</span> <span class="nf">disjunction</span> <span class="p">)</span><span class="o">*</span>
<span class="nf">yield_expr</span><span class="p">:</span>
<span class="o">|</span> <span class="k">'yield'</span> <span class="k">'from'</span> <span class="nf">expression</span>
<span class="o">|</span> <span class="k">'yield'</span> <span class="p">[</span><span class="nf">star_expressions</span><span class="p">]</span>
<span class="nf">arguments</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">args</span> <span class="p">[</span>','<span class="p">]</span> &')'
<span class="nf">args</span><span class="p">:</span>
<span class="o">|</span> ','<span class="o">.</span><span class="p">(</span><span class="nf">starred_expression</span> <span class="o">|</span> <span class="p">(</span> <span class="nf">assignment_expression</span> <span class="o">|</span> <span class="nf">expression</span> !':='<span class="p">)</span> !'='<span class="p">)</span><span class="o">+</span> <span class="p">[</span>',' <span class="nf">kwargs</span> <span class="p">]</span>
<span class="o">|</span> <span class="nf">kwargs</span>
<span class="nf">kwargs</span><span class="p">:</span>
<span class="o">|</span> ','<span class="o">.</span><span class="nf">kwarg_or_starred</span><span class="o">+</span> ',' ','<span class="o">.</span><span class="nf">kwarg_or_double_starred</span><span class="o">+</span>
<span class="o">|</span> ','<span class="o">.</span><span class="nf">kwarg_or_starred</span><span class="o">+</span>
<span class="o">|</span> ','<span class="o">.</span><span class="nf">kwarg_or_double_starred</span><span class="o">+</span>
<span class="nf">starred_expression</span><span class="p">:</span>
<span class="o">|</span> '*' <span class="nf">expression</span>
<span class="nf">kwarg_or_starred</span><span class="p">:</span>
<span class="o">|</span> NAME '=' <span class="nf">expression</span>
<span class="o">|</span> <span class="nf">starred_expression</span>
<span class="nf">kwarg_or_double_starred</span><span class="p">:</span>
<span class="o">|</span> NAME '=' <span class="nf">expression</span>
<span class="o">|</span> '**' <span class="nf">expression</span>
<span class="c c-Singleline"># NOTE: star_targets may contain *bitwise_or, targets may not.</span>
<span class="nf">star_targets</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">star_target</span> !','
<span class="o">|</span> <span class="nf">star_target</span> <span class="p">(</span>',' <span class="nf">star_target</span> <span class="p">)</span><span class="o">*</span> <span class="p">[</span>','<span class="p">]</span>
<span class="nf">star_targets_list_seq</span><span class="p">:</span> ','<span class="o">.</span><span class="nf">star_target</span><span class="o">+</span> <span class="p">[</span>','<span class="p">]</span>
<span class="nf">star_targets_tuple_seq</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">star_target</span> <span class="p">(</span>',' <span class="nf">star_target</span> <span class="p">)</span><span class="o">+</span> <span class="p">[</span>','<span class="p">]</span>
<span class="o">|</span> <span class="nf">star_target</span> ','
<span class="nf">star_target</span><span class="p">:</span>
<span class="o">|</span> '*' <span class="p">(</span>!'*' <span class="nf">star_target</span><span class="p">)</span>
<span class="o">|</span> <span class="nf">target_with_star_atom</span>
<span class="nf">target_with_star_atom</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">t_primary</span> '.' NAME !<span class="nf">t_lookahead</span>
<span class="o">|</span> <span class="nf">t_primary</span> '[' <span class="nf">slices</span> ']' !<span class="nf">t_lookahead</span>
<span class="o">|</span> <span class="nf">star_atom</span>
<span class="nf">star_atom</span><span class="p">:</span>
<span class="o">|</span> NAME
<span class="o">|</span> '(' <span class="nf">target_with_star_atom</span> ')'
<span class="o">|</span> '(' <span class="p">[</span><span class="nf">star_targets_tuple_seq</span><span class="p">]</span> ')'
<span class="o">|</span> '[' <span class="p">[</span><span class="nf">star_targets_list_seq</span><span class="p">]</span> ']'
<span class="nf">single_target</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">single_subscript_attribute_target</span>
<span class="o">|</span> NAME
<span class="o">|</span> '(' <span class="nf">single_target</span> ')'
<span class="nf">single_subscript_attribute_target</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">t_primary</span> '.' NAME !<span class="nf">t_lookahead</span>
<span class="o">|</span> <span class="nf">t_primary</span> '[' <span class="nf">slices</span> ']' !<span class="nf">t_lookahead</span>
<span class="nf">del_targets</span><span class="p">:</span> ','<span class="o">.</span><span class="nf">del_target</span><span class="o">+</span> <span class="p">[</span>','<span class="p">]</span>
<span class="nf">del_target</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">t_primary</span> '.' NAME !<span class="nf">t_lookahead</span>
<span class="o">|</span> <span class="nf">t_primary</span> '[' <span class="nf">slices</span> ']' !<span class="nf">t_lookahead</span>
<span class="o">|</span> <span class="nf">del_t_atom</span>
<span class="nf">del_t_atom</span><span class="p">:</span>
<span class="o">|</span> NAME
<span class="o">|</span> '(' <span class="nf">del_target</span> ')'
<span class="o">|</span> '(' <span class="p">[</span><span class="nf">del_targets</span><span class="p">]</span> ')'
<span class="o">|</span> '[' <span class="p">[</span><span class="nf">del_targets</span><span class="p">]</span> ']'
<span class="nf">t_primary</span><span class="p">:</span>
<span class="o">|</span> <span class="nf">t_primary</span> '.' NAME &<span class="nf">t_lookahead</span>
<span class="o">|</span> <span class="nf">t_primary</span> '[' <span class="nf">slices</span> ']' &<span class="nf">t_lookahead</span>
<span class="o">|</span> <span class="nf">t_primary</span> <span class="nf">genexp</span> &<span class="nf">t_lookahead</span>
<span class="o">|</span> <span class="nf">t_primary</span> '(' <span class="p">[</span><span class="nf">arguments</span><span class="p">]</span> ')' &<span class="nf">t_lookahead</span>
<span class="o">|</span> <span class="nf">atom</span> &<span class="nf">t_lookahead</span>
<span class="nf">t_lookahead</span><span class="p">:</span> '(' <span class="o">|</span> '[' <span class="o">|</span> '.'
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