1 # Grammar for 2to3. This grammar supports Python 2.x and 3.x. 2 3 # Note: Changing the grammar specified in this file will most likely 4 # require corresponding changes in the parser module 5 # (../Modules/parsermodule.c). If you can't make the changes to 6 # that module yourself, please co-ordinate the required changes 7 # with someone who can; ask around on python-dev for help. Fred 8 # Drake <fdrake (a] acm.org> will probably be listening there. 9 10 # NOTE WELL: You should also follow all the steps listed in PEP 306, 11 # "How to Change Python's Grammar" 12 13 # Commands for Kees Blom's railroad program 14 #diagram:token NAME 15 #diagram:token NUMBER 16 #diagram:token STRING 17 #diagram:token NEWLINE 18 #diagram:token ENDMARKER 19 #diagram:token INDENT 20 #diagram:output\input python.bla 21 #diagram:token DEDENT 22 #diagram:output\textwidth 20.04cm\oddsidemargin 0.0cm\evensidemargin 0.0cm 23 #diagram:rules 24 25 # Start symbols for the grammar: 26 # file_input is a module or sequence of commands read from an input file; 27 # single_input is a single interactive statement; 28 # eval_input is the input for the eval() and input() functions. 29 # NB: compound_stmt in single_input is followed by extra NEWLINE! 30 file_input: (NEWLINE | stmt)* ENDMARKER 31 single_input: NEWLINE | simple_stmt | compound_stmt NEWLINE 32 eval_input: testlist NEWLINE* ENDMARKER 33 34 decorator: '@' dotted_name [ '(' [arglist] ')' ] NEWLINE 35 decorators: decorator+ 36 decorated: decorators (classdef | funcdef) 37 funcdef: 'def' NAME parameters ['->' test] ':' suite 38 parameters: '(' [typedargslist] ')' 39 typedargslist: ((tfpdef ['=' test] ',')* 40 ('*' [tname] (',' tname ['=' test])* [',' '**' tname] | '**' tname) 41 | tfpdef ['=' test] (',' tfpdef ['=' test])* [',']) 42 tname: NAME [':' test] 43 tfpdef: tname | '(' tfplist ')' 44 tfplist: tfpdef (',' tfpdef)* [','] 45 varargslist: ((vfpdef ['=' test] ',')* 46 ('*' [vname] (',' vname ['=' test])* [',' '**' vname] | '**' vname) 47 | vfpdef ['=' test] (',' vfpdef ['=' test])* [',']) 48 vname: NAME 49 vfpdef: vname | '(' vfplist ')' 50 vfplist: vfpdef (',' vfpdef)* [','] 51 52 stmt: simple_stmt | compound_stmt 53 simple_stmt: small_stmt (';' small_stmt)* [';'] NEWLINE 54 small_stmt: (expr_stmt | print_stmt | del_stmt | pass_stmt | flow_stmt | 55 import_stmt | global_stmt | exec_stmt | assert_stmt) 56 expr_stmt: testlist_star_expr (augassign (yield_expr|testlist) | 57 ('=' (yield_expr|testlist_star_expr))*) 58 testlist_star_expr: (test|star_expr) (',' (test|star_expr))* [','] 59 augassign: ('+=' | '-=' | '*=' | '/=' | '%=' | '&=' | '|=' | '^=' | 60 '<<=' | '>>=' | '**=' | '//=') 61 # For normal assignments, additional restrictions enforced by the interpreter 62 print_stmt: 'print' ( [ test (',' test)* [','] ] | 63 '>>' test [ (',' test)+ [','] ] ) 64 del_stmt: 'del' exprlist 65 pass_stmt: 'pass' 66 flow_stmt: break_stmt | continue_stmt | return_stmt | raise_stmt | yield_stmt 67 break_stmt: 'break' 68 continue_stmt: 'continue' 69 return_stmt: 'return' [testlist] 70 yield_stmt: yield_expr 71 raise_stmt: 'raise' [test ['from' test | ',' test [',' test]]] 72 import_stmt: import_name | import_from 73 import_name: 'import' dotted_as_names 74 import_from: ('from' ('.'* dotted_name | '.'+) 75 'import' ('*' | '(' import_as_names ')' | import_as_names)) 76 import_as_name: NAME ['as' NAME] 77 dotted_as_name: dotted_name ['as' NAME] 78 import_as_names: import_as_name (',' import_as_name)* [','] 79 dotted_as_names: dotted_as_name (',' dotted_as_name)* 80 dotted_name: NAME ('.' NAME)* 81 global_stmt: ('global' | 'nonlocal') NAME (',' NAME)* 82 exec_stmt: 'exec' expr ['in' test [',' test]] 83 assert_stmt: 'assert' test [',' test] 84 85 compound_stmt: if_stmt | while_stmt | for_stmt | try_stmt | with_stmt | funcdef | classdef | decorated 86 if_stmt: 'if' test ':' suite ('elif' test ':' suite)* ['else' ':' suite] 87 while_stmt: 'while' test ':' suite ['else' ':' suite] 88 for_stmt: 'for' exprlist 'in' testlist ':' suite ['else' ':' suite] 89 try_stmt: ('try' ':' suite 90 ((except_clause ':' suite)+ 91 ['else' ':' suite] 92 ['finally' ':' suite] | 93 'finally' ':' suite)) 94 with_stmt: 'with' with_item (',' with_item)* ':' suite 95 with_item: test ['as' expr] 96 with_var: 'as' expr 97 # NB compile.c makes sure that the default except clause is last 98 except_clause: 'except' [test [(',' | 'as') test]] 99 suite: simple_stmt | NEWLINE INDENT stmt+ DEDENT 100 101 # Backward compatibility cruft to support: 102 # [ x for x in lambda: True, lambda: False if x() ] 103 # even while also allowing: 104 # lambda x: 5 if x else 2 105 # (But not a mix of the two) 106 testlist_safe: old_test [(',' old_test)+ [',']] 107 old_test: or_test | old_lambdef 108 old_lambdef: 'lambda' [varargslist] ':' old_test 109 110 test: or_test ['if' or_test 'else' test] | lambdef 111 or_test: and_test ('or' and_test)* 112 and_test: not_test ('and' not_test)* 113 not_test: 'not' not_test | comparison 114 comparison: expr (comp_op expr)* 115 comp_op: '<'|'>'|'=='|'>='|'<='|'<>'|'!='|'in'|'not' 'in'|'is'|'is' 'not' 116 star_expr: '*' expr 117 expr: xor_expr ('|' xor_expr)* 118 xor_expr: and_expr ('^' and_expr)* 119 and_expr: shift_expr ('&' shift_expr)* 120 shift_expr: arith_expr (('<<'|'>>') arith_expr)* 121 arith_expr: term (('+'|'-') term)* 122 term: factor (('*'|'/'|'%'|'//') factor)* 123 factor: ('+'|'-'|'~') factor | power 124 power: atom trailer* ['**' factor] 125 atom: ('(' [yield_expr|testlist_gexp] ')' | 126 '[' [listmaker] ']' | 127 '{' [dictsetmaker] '}' | 128 '`' testlist1 '`' | 129 NAME | NUMBER | STRING+ | '.' '.' '.') 130 listmaker: (test|star_expr) ( comp_for | (',' (test|star_expr))* [','] ) 131 testlist_gexp: (test|star_expr) ( comp_for | (',' (test|star_expr))* [','] ) 132 lambdef: 'lambda' [varargslist] ':' test 133 trailer: '(' [arglist] ')' | '[' subscriptlist ']' | '.' NAME 134 subscriptlist: subscript (',' subscript)* [','] 135 subscript: test | [test] ':' [test] [sliceop] 136 sliceop: ':' [test] 137 exprlist: (expr|star_expr) (',' (expr|star_expr))* [','] 138 testlist: test (',' test)* [','] 139 dictsetmaker: ( (test ':' test (comp_for | (',' test ':' test)* [','])) | 140 (test (comp_for | (',' test)* [','])) ) 141 142 classdef: 'class' NAME ['(' [arglist] ')'] ':' suite 143 144 arglist: (argument ',')* (argument [','] 145 |'*' test (',' argument)* [',' '**' test] 146 |'**' test) 147 argument: test [comp_for] | test '=' test # Really [keyword '='] test 148 149 comp_iter: comp_for | comp_if 150 comp_for: 'for' exprlist 'in' testlist_safe [comp_iter] 151 comp_if: 'if' old_test [comp_iter] 152 153 testlist1: test (',' test)* 154 155 # not used in grammar, but may appear in "node" passed from Parser to Compiler 156 encoding_decl: NAME 157 158 yield_expr: 'yield' [testlist] 159
