cpython/Lib/lib2to3/Grammar.txt

157 lines
6.2 KiB
Plaintext
Raw Normal View History

2008-03-19 01:43:46 -03:00
# 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"
# Commands for Kees Blom's railroad program
#diagram:token NAME
#diagram:token NUMBER
#diagram:token STRING
#diagram:token NEWLINE
#diagram:token ENDMARKER
#diagram:token INDENT
#diagram:output\input python.bla
#diagram:token DEDENT
#diagram:output\textwidth 20.04cm\oddsidemargin 0.0cm\evensidemargin 0.0cm
#diagram:rules
# Start symbols for the grammar:
# file_input is a module or sequence of commands read from an input file;
# single_input is a single interactive statement;
# eval_input is the input for the eval() and input() functions.
# NB: compound_stmt in single_input is followed by extra NEWLINE!
file_input: (NEWLINE | stmt)* ENDMARKER
single_input: NEWLINE | simple_stmt | compound_stmt NEWLINE
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] ',')*
('*' [tname] (',' tname ['=' test])* [',' '**' tname] | '**' tname)
| tfpdef ['=' test] (',' tfpdef ['=' test])* [','])
tname: NAME [':' test]
tfpdef: tname | '(' tfplist ')'
tfplist: tfpdef (',' tfpdef)* [',']
varargslist: ((vfpdef ['=' test] ',')*
('*' [vname] (',' vname ['=' test])* [',' '**' vname] | '**' vname)
| vfpdef ['=' test] (',' vfpdef ['=' test])* [','])
vname: NAME
vfpdef: vname | '(' vfplist ')'
vfplist: vfpdef (',' vfpdef)* [',']
stmt: simple_stmt | compound_stmt
simple_stmt: small_stmt (';' small_stmt)* [';'] NEWLINE
small_stmt: (expr_stmt | print_stmt | del_stmt | pass_stmt | flow_stmt |
import_stmt | global_stmt | exec_stmt | assert_stmt)
expr_stmt: testlist (augassign (yield_expr|testlist) |
('=' (yield_expr|testlist))*)
augassign: ('+=' | '-=' | '*=' | '/=' | '%=' | '&=' | '|=' | '^=' |
'<<=' | '>>=' | '**=' | '//=')
# For normal assignments, additional restrictions enforced by the interpreter
print_stmt: 'print' ( [ test (',' test)* [','] ] |
'>>' test [ (',' test)+ [','] ] )
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 | ',' test [',' test]]]
import_stmt: import_name | import_from
import_name: 'import' dotted_as_names
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' | 'nonlocal') NAME (',' NAME)*
exec_stmt: 'exec' expr ['in' test [',' test]]
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))
Merged revisions 72523,72950-72951,72994,73003,73033,73036-73040,73091-73093,73096,73179-73181,73192,73231,73244,73255-73256,73365 via svnmerge from svn+ssh://pythondev@svn.python.org/sandbox/trunk/2to3/lib2to3 ........ r72523 | benjamin.peterson | 2009-05-09 14:42:26 -0500 (Sat, 09 May 2009) | 1 line remove parenthesis ........ r72950 | benjamin.peterson | 2009-05-26 18:19:45 -0500 (Tue, 26 May 2009) | 1 line remove unused imports ........ r72951 | benjamin.peterson | 2009-05-26 18:27:00 -0500 (Tue, 26 May 2009) | 1 line this is no longer executable ........ r72994 | benjamin.peterson | 2009-05-28 15:32:54 -0500 (Thu, 28 May 2009) | 1 line fix test_all_fixers on Windows #6134 ........ r73003 | benjamin.peterson | 2009-05-28 21:57:28 -0500 (Thu, 28 May 2009) | 4 lines make 2to3 test utilities easier to use with other applications (3to2) Patch by Joe Amenta ........ r73033 | benjamin.peterson | 2009-05-29 16:58:32 -0500 (Fri, 29 May 2009) | 1 line update grammar for multi with statement ........ r73036 | benjamin.peterson | 2009-05-29 17:33:20 -0500 (Fri, 29 May 2009) | 1 line simplify fix_unicode ........ r73037 | benjamin.peterson | 2009-05-29 17:53:03 -0500 (Fri, 29 May 2009) | 1 line add custom error for pattern syntax errors ........ r73038 | benjamin.peterson | 2009-05-29 17:55:00 -0500 (Fri, 29 May 2009) | 1 line complain if details are attached to a token ........ r73039 | benjamin.peterson | 2009-05-29 18:00:28 -0500 (Fri, 29 May 2009) | 1 line add a test for whitespace ........ r73040 | benjamin.peterson | 2009-05-29 18:01:17 -0500 (Fri, 29 May 2009) | 1 line a fix for emacs highlighting ........ r73091 | benjamin.peterson | 2009-05-31 20:55:25 -0500 (Sun, 31 May 2009) | 1 line deprecate set_prefix() and get_prefix() in favor of a prefix property ........ r73092 | benjamin.peterson | 2009-05-31 21:00:51 -0500 (Sun, 31 May 2009) | 1 line change hideous java naming scheme ........ r73093 | benjamin.peterson | 2009-05-31 21:01:39 -0500 (Sun, 31 May 2009) | 1 line remove dated comment ........ r73096 | benjamin.peterson | 2009-05-31 21:40:53 -0500 (Sun, 31 May 2009) | 1 line group tests ........ r73179 | benjamin.peterson | 2009-06-03 13:09:53 -0500 (Wed, 03 Jun 2009) | 1 line handle the case where there's multiple trailers #6185 ........ r73180 | benjamin.peterson | 2009-06-03 13:18:05 -0500 (Wed, 03 Jun 2009) | 1 line scrap __main__ section ........ r73181 | benjamin.peterson | 2009-06-03 13:24:48 -0500 (Wed, 03 Jun 2009) | 1 line remove shebang lines and __main__ sections ........ r73192 | benjamin.peterson | 2009-06-03 19:16:30 -0500 (Wed, 03 Jun 2009) | 4 lines actually test something here Thanks to Joe Amenta for noticing.y ........ r73231 | benjamin.peterson | 2009-06-04 13:38:50 -0500 (Thu, 04 Jun 2009) | 1 line remove unused variable ........ r73244 | benjamin.peterson | 2009-06-05 08:39:25 -0500 (Fri, 05 Jun 2009) | 1 line allow fixers to give different options in setUp ........ r73255 | benjamin.peterson | 2009-06-06 11:23:46 -0500 (Sat, 06 Jun 2009) | 1 line fix the except fixer on one line suites #6222 ........ r73256 | benjamin.peterson | 2009-06-06 11:27:40 -0500 (Sat, 06 Jun 2009) | 1 line test one-line else and finally clauses ........ r73365 | benjamin.peterson | 2009-06-11 17:01:32 -0500 (Thu, 11 Jun 2009) | 1 line normalize whitespace ........
2009-06-11 19:06:46 -03:00
with_stmt: 'with' with_item (',' with_item)* ':' suite
with_item: test ['as' expr]
2008-03-19 01:43:46 -03:00
with_var: 'as' expr
# NB compile.c makes sure that the default except clause is last
except_clause: 'except' [test [(',' | 'as') test]]
suite: simple_stmt | NEWLINE INDENT stmt+ DEDENT
# Backward compatibility cruft to support:
# [ x for x in lambda: True, lambda: False if x() ]
# even while also allowing:
# lambda x: 5 if x else 2
# (But not a mix of the two)
testlist_safe: old_test [(',' old_test)+ [',']]
old_test: or_test | old_lambdef
old_lambdef: 'lambda' [varargslist] ':' old_test
test: or_test ['if' or_test 'else' test] | lambdef
or_test: and_test ('or' and_test)*
and_test: not_test ('and' not_test)*
not_test: 'not' not_test | comparison
comparison: expr (comp_op expr)*
comp_op: '<'|'>'|'=='|'>='|'<='|'<>'|'!='|'in'|'not' 'in'|'is'|'is' 'not'
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_gexp] ')' |
'[' [listmaker] ']' |
'{' [dictsetmaker] '}' |
'`' testlist1 '`' |
NAME | NUMBER | STRING+ | '.' '.' '.')
listmaker: test ( comp_for | (',' test)* [','] )
testlist_gexp: test ( comp_for | (',' test)* [','] )
lambdef: 'lambda' [varargslist] ':' test
trailer: '(' [arglist] ')' | '[' subscriptlist ']' | '.' NAME
subscriptlist: subscript (',' subscript)* [',']
subscript: test | [test] ':' [test] [sliceop]
sliceop: ':' [test]
exprlist: expr (',' expr)* [',']
testlist: test (',' test)* [',']
dictsetmaker: ( (test ':' test (comp_for | (',' test ':' test)* [','])) |
(test (comp_for | (',' test)* [','])) )
classdef: 'class' NAME ['(' [arglist] ')'] ':' suite
arglist: (argument ',')* (argument [',']
|'*' test (',' argument)* [',' '**' test]
|'**' test)
2008-03-19 01:43:46 -03:00
argument: test [comp_for] | test '=' test # Really [keyword '='] test
comp_iter: comp_for | comp_if
comp_for: 'for' exprlist 'in' testlist_safe [comp_iter]
comp_if: 'if' old_test [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]