diff options
Diffstat (limited to 'lib/python2.7/lib2to3/Grammar.txt')
| -rw-r--r-- | lib/python2.7/lib2to3/Grammar.txt | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/lib/python2.7/lib2to3/Grammar.txt b/lib/python2.7/lib2to3/Grammar.txt new file mode 100644 index 0000000..9be7c9f --- /dev/null +++ b/lib/python2.7/lib2to3/Grammar.txt @@ -0,0 +1,170 @@ +# Grammar for 2to3. This grammar supports Python 2.x and 3.x. + +# 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_star_expr (augassign (yield_expr|testlist) | + ('=' (yield_expr|testlist_star_expr))*) +testlist_star_expr: (test|star_expr) (',' (test|star_expr))* [','] +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)) +with_stmt: 'with' with_item (',' with_item)* ':' suite +with_item: test ['as' expr] +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' +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_gexp] ')' | + '[' [listmaker] ']' | + '{' [dictsetmaker] '}' | + '`' testlist1 '`' | + NAME | NUMBER | STRING+ | '.' '.' '.') +listmaker: (test|star_expr) ( comp_for | (',' (test|star_expr))* [','] ) +testlist_gexp: (test|star_expr) ( comp_for | (',' (test|star_expr))* [','] ) +lambdef: 'lambda' [varargslist] ':' test +trailer: '(' [arglist] ')' | '[' subscriptlist ']' | '.' NAME +subscriptlist: subscript (',' subscript)* [','] +subscript: test | [test] ':' [test] [sliceop] +sliceop: ':' [test] +exprlist: (expr|star_expr) (',' (expr|star_expr))* [','] +testlist: test (',' test)* [','] +dictsetmaker: ( ((test ':' test | '**' expr) + (comp_for | (',' (test ':' test | '**' expr))* [','])) | + ((test | star_expr) + (comp_for | (',' (test | star_expr))* [','])) ) + +classdef: 'class' NAME ['(' [arglist] ')'] ':' suite + +arglist: argument (',' argument)* [','] + +# "test '=' test" is really "keyword '=' test", but we have no such token. +# These need to be in a single rule to avoid grammar that is ambiguous +# to our LL(1) parser. Even though 'test' includes '*expr' in star_expr, +# we explicitly match '*' here, too, to give it proper precedence. +# Illegal combinations and orderings are blocked in ast.c: +# multiple (test comp_for) arguments are blocked; keyword unpackings +# that precede iterable unpackings are blocked; etc. +argument: ( test [comp_for] | + test '=' test | + '**' expr | + star_expr ) + +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' [yield_arg] +yield_arg: 'from' test | testlist |