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anthonybaxter
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PEP-0318, @decorator-style. In Guido's words:
"@ seems the syntax that everybody can hate equally" Implementation by Mark Russell, from SF #979728. git-svn-id: http://svn.python.org/projects/python/trunk@36712 6015fed2-1504-0410-9fe1-9d1591cc4771
1 parent c92150a commit 79b907e

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Lines changed: 2562 additions & 1932 deletions

‎Doc/lib/asttable.tex‎

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@@ -73,6 +73,9 @@
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\lineiii{Continue}{}{}
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\hline
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\lineiii{Decorators}{\member{nodes}}{List of function decorator expressions}
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\hline
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\lineiii{Dict}{\member{items}}{}
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\hline
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@@ -101,7 +104,8 @@
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\lineiii{}{\member{names}}{}
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\hline
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\lineiii{Function}{\member{name}}{name used in def, a string}
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\lineiii{Function}{\member{decorators}}{\class{Decorators} or \code{None}}
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\lineiii{}{\member{name}}{name used in def, a string}
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\lineiii{}{\member{argnames}}{list of argument names, as strings}
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\lineiii{}{\member{defaults}}{list of default values}
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\lineiii{}{\member{flags}}{xxx}

‎Doc/lib/libfuncs.tex‎

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@@ -109,10 +109,14 @@ \section{Built-in Functions \label{built-in-funcs}}
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\begin{verbatim}
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class C:
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@classmethod
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def f(cls, arg1, arg2, ...): ...
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f = classmethod(f)
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\end{verbatim}
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The \code{@classmethod} form is a function decorator -- see the description
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of function definitions in chapter 7 of the
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\citetitle[../ref/ref.html]{Python Reference Manual} for details.
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It can be called either on the class (such as \code{C.f()}) or on an
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instance (such as \code{C().f()}). The instance is ignored except for
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its class.
@@ -122,6 +126,7 @@ \section{Built-in Functions \label{built-in-funcs}}
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Class methods are different than \Cpp{} or Java static methods.
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If you want those, see \function{staticmethod()} in this section.
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\versionadded{2.2}
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Function decorator syntax added in version 2.4.
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\end{funcdesc}
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\begin{funcdesc}{cmp}{x, y}
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\begin{verbatim}
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class C:
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@staticmethod
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def f(arg1, arg2, ...): ...
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f = staticmethod(f)
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\end{verbatim}
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The \code{@staticmethod} form is a function decorator -- see the description
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of function definitions in chapter 7 of the
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\citetitle[../ref/ref.html]{Python Reference Manual} for details.
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It can be called either on the class (such as \code{C.f()}) or on an
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instance (such as \code{C().f()}). The instance is ignored except
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for its class.

‎Doc/ref/ref7.tex‎

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@@ -315,8 +315,12 @@ \section{Function definitions\label{function}}
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\begin{productionlist}
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\production{funcdef}
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{"def" \token{funcname} "(" [\token{parameter_list}] ")"
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{[\token{decorators}] "def" \token{funcname} "(" [\token{parameter_list}] ")"
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":" \token{suite}}
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\production{decorators}
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{\token{decorator} ([NEWLINE] \token{decorator})* NEWLINE}
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\production{decorator}
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{"@" \token{dotted_name} ["(" [\token{argument_list} [","]] ")"]}
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\production{parameter_list}
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{(\token{defparameter} ",")*}
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\productioncont{("*" \token{identifier} [, "**" \token{identifier}]}
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The function definition does not execute the function body; this gets
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executed only when the function is called.
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A function definition may be wrapped by one or more decorator expressions.
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Decorator expressions are evaluated when the function is defined, in the scope
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that contains the function definition. The result must be a callable,
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which is invoked with the function object as the only argument.
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The returned value is bound to the function name instead of the function
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object. If there are multiple decorators, they are applied in reverse
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order. For example, the following code:
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\begin{verbatim}
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@f1
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@f2
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def func(): pass
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\end{verbatim}
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is equivalent to:
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\begin{verbatim}
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def func(): pass
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func = f2(f1(func))
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\end{verbatim}
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When one or more top-level parameters have the form \var{parameter}
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\code{=} \var{expression}, the function is said to have ``default
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parameter values.'' For a parameter with a

‎Grammar/Grammar‎

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@@ -28,7 +28,9 @@ single_input: NEWLINE | simple_stmt | compound_stmt NEWLINE
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file_input: (NEWLINE | stmt)* ENDMARKER
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eval_input: testlist NEWLINE* ENDMARKER
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funcdef: 'def' NAME parameters ':' suite
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decorator: '@' dotted_name [ '(' [arglist] ')' ]
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decorators: decorator ([NEWLINE] decorator)* NEWLINE
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funcdef: [decorators] 'def' NAME parameters ':' suite
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parameters: '(' [varargslist] ')'
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varargslist: (fpdef ['=' test] ',')* ('*' NAME [',' '**' NAME] | '**' NAME) | fpdef ['=' test] (',' fpdef ['=' test])* [',']
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fpdef: NAME | '(' fplist ')'

‎Include/graminit.h‎

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@@ -1,72 +1,74 @@
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#define single_input 256
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#define file_input 257
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#define eval_input 258
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#define funcdef 259
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#define parameters 260
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#define varargslist 261
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#define fpdef 262
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#define fplist 263
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#define stmt 264
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#define simple_stmt 265
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#define small_stmt 266
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#define expr_stmt 267
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#define augassign 268
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#define print_stmt 269
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#define del_stmt 270
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#define pass_stmt 271
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#define flow_stmt 272
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#define break_stmt 273
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#define continue_stmt 274
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#define return_stmt 275
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#define yield_stmt 276
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#define raise_stmt 277
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#define import_stmt 278
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#define import_as_name 279
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#define dotted_as_name 280
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#define dotted_name 281
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#define global_stmt 282
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#define exec_stmt 283
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#define assert_stmt 284
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#define compound_stmt 285
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#define if_stmt 286
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#define while_stmt 287
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#define for_stmt 288
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#define try_stmt 289
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#define except_clause 290
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#define suite 291
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#define test 292
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#define and_test 293
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#define not_test 294
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#define comparison 295
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#define comp_op 296
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#define expr 297
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#define xor_expr 298
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#define and_expr 299
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#define shift_expr 300
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#define arith_expr 301
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#define term 302
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#define factor 303
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#define power 304
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#define atom 305
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#define listmaker 306
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#define testlist_gexp 307
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#define lambdef 308
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#define trailer 309
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#define subscriptlist 310
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#define subscript 311
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#define sliceop 312
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#define exprlist 313
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#define testlist 314
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#define testlist_safe 315
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#define dictmaker 316
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#define classdef 317
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#define arglist 318
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#define argument 319
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#define list_iter 320
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#define list_for 321
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#define list_if 322
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#define gen_iter 323
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#define gen_for 324
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#define gen_if 325
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#define testlist1 326
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#define encoding_decl 327
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#define decorator 259
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#define decorators 260
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#define funcdef 261
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#define parameters 262
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#define varargslist 263
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#define fpdef 264
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#define fplist 265
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#define stmt 266
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#define simple_stmt 267
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#define small_stmt 268
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#define expr_stmt 269
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#define augassign 270
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#define print_stmt 271
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#define del_stmt 272
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#define pass_stmt 273
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#define flow_stmt 274
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#define break_stmt 275
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#define continue_stmt 276
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#define return_stmt 277
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#define yield_stmt 278
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#define raise_stmt 279
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#define import_stmt 280
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#define import_as_name 281
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#define dotted_as_name 282
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#define dotted_name 283
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#define global_stmt 284
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#define exec_stmt 285
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#define assert_stmt 286
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#define compound_stmt 287
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#define if_stmt 288
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#define while_stmt 289
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#define for_stmt 290
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#define try_stmt 291
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#define except_clause 292
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#define suite 293
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#define test 294
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#define and_test 295
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#define not_test 296
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#define comparison 297
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#define comp_op 298
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#define expr 299
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#define xor_expr 300
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#define and_expr 301
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#define shift_expr 302
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#define arith_expr 303
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#define term 304
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#define factor 305
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#define power 306
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#define atom 307
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#define listmaker 308
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#define testlist_gexp 309
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#define lambdef 310
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#define trailer 311
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#define subscriptlist 312
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#define subscript 313
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#define sliceop 314
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#define exprlist 315
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#define testlist 316
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#define testlist_safe 317
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#define dictmaker 318
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#define classdef 319
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#define arglist 320
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#define argument 321
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#define list_iter 322
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#define list_for 323
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#define list_if 324
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#define gen_iter 325
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#define gen_for 326
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#define gen_if 327
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#define testlist1 328
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#define encoding_decl 329

‎Include/node.h‎

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@@ -22,7 +22,9 @@ PyAPI_FUNC(void) PyNode_Free(node *n);
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/* Node access functions */
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#define NCH(n) ((n)->n_nchildren)
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#define CHILD(n, i) (&(n)->n_child[i])
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#define RCHILD(n, i) (CHILD(n, NCH(n) + i))
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#define TYPE(n) ((n)->n_type)
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#define STR(n) ((n)->n_str)
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‎Include/token.h‎

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@@ -57,10 +57,11 @@ extern "C" {
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#define DOUBLESTAREQUAL 47
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#define DOUBLESLASH 48
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#define DOUBLESLASHEQUAL 49
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#define AT 50
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/* Don't forget to update the table _PyParser_TokenNames in tokenizer.c! */
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#define OP 50
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#define ERRORTOKEN 51
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#define N_TOKENS 52
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#define OP 51
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#define ERRORTOKEN 52
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#define N_TOKENS 53
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/* Special definitions for cooperation with parser */
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