| # Grammar for Python |
| |
| # Note: Changing the grammar specified in this file will most likely |
| # require corresponding changes in the parser module |
| # (../Modules/parsermodule.c). If you can't make the changes to |
| # that module yourself, please co-ordinate the required changes |
| # with someone who can; ask around on python-dev for help. Fred |
| # Drake <fdrake@acm.org> will probably be listening there. |
| |
| # NOTE WELL: You should also follow all the steps listed in PEP 306, |
| # "How to Change Python's Grammar" |
| |
| # Start symbols for the grammar: |
| # single_input is a single interactive statement; |
| # file_input is a module or sequence of commands read from an input file; |
| # eval_input is the input for the eval() and input() functions. |
| # NB: compound_stmt in single_input is followed by extra NEWLINE! |
| single_input: NEWLINE | simple_stmt | compound_stmt NEWLINE |
| file_input: (NEWLINE | stmt)* ENDMARKER |
| eval_input: testlist NEWLINE* ENDMARKER |
| |
| decorator: '@' dotted_name [ '(' [arglist] ')' ] NEWLINE |
| decorators: decorator+ |
| decorated: decorators (classdef | funcdef) |
| funcdef: 'def' NAME parameters ['->' test] ':' suite |
| parameters: '(' [typedargslist] ')' |
| typedargslist: ((tfpdef ['=' test] ',')* |
| ('*' [tfpdef] (',' tfpdef ['=' test])* [',' '**' tfpdef] | '**' tfpdef) |
| | tfpdef ['=' test] (',' tfpdef ['=' test])* [',']) |
| tfpdef: NAME [':' test] |
| varargslist: ((vfpdef ['=' test] ',')* |
| ('*' [vfpdef] (',' vfpdef ['=' test])* [',' '**' vfpdef] | '**' vfpdef) |
| | vfpdef ['=' test] (',' vfpdef ['=' test])* [',']) |
| vfpdef: NAME |
| |
| stmt: simple_stmt | compound_stmt |
| simple_stmt: small_stmt (';' small_stmt)* [';'] NEWLINE |
| small_stmt: (expr_stmt | del_stmt | pass_stmt | flow_stmt | |
| import_stmt | global_stmt | nonlocal_stmt | assert_stmt) |
| expr_stmt: testlist (augassign (yield_expr|testlist) | |
| ('=' (yield_expr|testlist))*) |
| augassign: ('+=' | '-=' | '*=' | '/=' | '%=' | '&=' | '|=' | '^=' | |
| '<<=' | '>>=' | '**=' | '//=') |
| # For normal assignments, additional restrictions enforced by the interpreter |
| del_stmt: 'del' exprlist |
| pass_stmt: 'pass' |
| flow_stmt: break_stmt | continue_stmt | return_stmt | raise_stmt | yield_stmt |
| break_stmt: 'break' |
| continue_stmt: 'continue' |
| return_stmt: 'return' [testlist] |
| yield_stmt: yield_expr |
| raise_stmt: 'raise' [test ['from' test]] |
| import_stmt: import_name | import_from |
| import_name: 'import' dotted_as_names |
| # note below: the ('.' | '...') is necessary because '...' is tokenized as ELLIPSIS |
| import_from: ('from' (('.' | '...')* dotted_name | ('.' | '...')+) |
| 'import' ('*' | '(' import_as_names ')' | import_as_names)) |
| import_as_name: NAME ['as' NAME] |
| dotted_as_name: dotted_name ['as' NAME] |
| import_as_names: import_as_name (',' import_as_name)* [','] |
| dotted_as_names: dotted_as_name (',' dotted_as_name)* |
| dotted_name: NAME ('.' NAME)* |
| global_stmt: 'global' NAME (',' NAME)* |
| nonlocal_stmt: 'nonlocal' NAME (',' NAME)* |
| assert_stmt: 'assert' test [',' test] |
| |
| compound_stmt: if_stmt | while_stmt | for_stmt | try_stmt | with_stmt | funcdef | classdef | decorated |
| if_stmt: 'if' test ':' suite ('elif' test ':' suite)* ['else' ':' suite] |
| while_stmt: 'while' test ':' suite ['else' ':' suite] |
| for_stmt: 'for' exprlist 'in' testlist ':' suite ['else' ':' suite] |
| try_stmt: ('try' ':' suite |
| ((except_clause ':' suite)+ |
| ['else' ':' suite] |
| ['finally' ':' suite] | |
| 'finally' ':' suite)) |
| with_stmt: 'with' test [ with_var ] ':' suite |
| with_var: 'as' expr |
| # NB compile.c makes sure that the default except clause is last |
| except_clause: 'except' [test ['as' NAME]] |
| suite: simple_stmt | NEWLINE INDENT stmt+ DEDENT |
| |
| test: or_test ['if' or_test 'else' test] | lambdef |
| test_nocond: or_test | lambdef_nocond |
| lambdef: 'lambda' [varargslist] ':' test |
| lambdef_nocond: 'lambda' [varargslist] ':' test_nocond |
| or_test: and_test ('or' and_test)* |
| and_test: not_test ('and' not_test)* |
| not_test: 'not' not_test | comparison |
| comparison: star_expr (comp_op star_expr)* |
| comp_op: '<'|'>'|'=='|'>='|'<='|'<>'|'!='|'in'|'not' 'in'|'is'|'is' 'not' |
| star_expr: ['*'] expr |
| expr: xor_expr ('|' xor_expr)* |
| xor_expr: and_expr ('^' and_expr)* |
| and_expr: shift_expr ('&' shift_expr)* |
| shift_expr: arith_expr (('<<'|'>>') arith_expr)* |
| arith_expr: term (('+'|'-') term)* |
| term: factor (('*'|'/'|'%'|'//') factor)* |
| factor: ('+'|'-'|'~') factor | power |
| power: atom trailer* ['**' factor] |
| atom: ('(' [yield_expr|testlist_comp] ')' | |
| '[' [testlist_comp] ']' | |
| '{' [dictorsetmaker] '}' | |
| NAME | NUMBER | STRING+ | '...' | 'None' | 'True' | 'False') |
| testlist_comp: test ( comp_for | (',' test)* [','] ) |
| trailer: '(' [arglist] ')' | '[' subscriptlist ']' | '.' NAME |
| subscriptlist: subscript (',' subscript)* [','] |
| subscript: test | [test] ':' [test] [sliceop] |
| sliceop: ':' [test] |
| exprlist: star_expr (',' star_expr)* [','] |
| testlist: test (',' test)* [','] |
| dictorsetmaker: ( (test ':' test (comp_for | (',' test ':' test)* [','])) | |
| (test (comp_for | (',' test)* [','])) ) |
| |
| classdef: 'class' NAME ['(' [arglist] ')'] ':' suite |
| |
| arglist: (argument ',')* (argument [','] |
| |'*' test (',' argument)* [',' '**' test] |
| |'**' test) |
| argument: test [comp_for] | test '=' test # Really [keyword '='] test |
| |
| comp_iter: comp_for | comp_if |
| comp_for: 'for' exprlist 'in' or_test [comp_iter] |
| comp_if: 'if' test_nocond [comp_iter] |
| |
| testlist1: test (',' test)* |
| |
| # not used in grammar, but may appear in "node" passed from Parser to Compiler |
| encoding_decl: NAME |
| |
| yield_expr: 'yield' [testlist] |