[Python-checkins] CVS: python/dist/src/Grammar Grammar,1.43,1.44

2001年8月07日 22:00:19 -0700

Update of /cvsroot/python/python/dist/src/Grammar
In directory usw-pr-cvs1:/tmp/cvs-serv23513/Grammar
Modified Files:
	Grammar 
Log Message:
Implement PEP 238 in its (almost) full glory.
This introduces:
- A new operator // that means floor division (the kind of division
 where 1/2 is 0).
- The "future division" statement ("from __future__ import division)
 which changes the meaning of the / operator to implement "true
 division" (where 1/2 is 0.5).
- New overloadable operators __truediv__ and __floordiv__.
- New slots in the PyNumberMethods struct for true and floor division,
 new abstract APIs for them, new opcodes, and so on.
I emphasize that without the future division statement, the semantics
of / will remain unchanged until Python 3.0.
Not yet implemented are warnings (default off) when / is used with int
or long arguments.
This has been on display since 7/31 as SF patch #443474.
Flames to /dev/null.
Index: Grammar
===================================================================
RCS file: /cvsroot/python/python/dist/src/Grammar/Grammar,v
retrieving revision 1.43
retrieving revision 1.44
diff -C2 -d -r1.43 -r1.44
*** Grammar	2001年06月18日 22:08:13	1.43
--- Grammar	2001年08月08日 05:00:17	1.44
***************
*** 39,43 ****
 small_stmt: expr_stmt | print_stmt | del_stmt | pass_stmt | flow_stmt | import_stmt | global_stmt | exec_stmt | assert_stmt
 expr_stmt: testlist (augassign testlist | ('=' testlist)*)
! augassign: '+=' | '-=' | '*=' | '/=' | '%=' | '&=' | '|=' | '^=' | '<<=' | '>>=' | '**='
 # For normal assignments, additional restrictions enforced by the interpreter
 print_stmt: 'print' ( [ test (',' test)* [','] ] | '>>' test [ (',' test)+ [','] ] )
--- 39,43 ----
 small_stmt: expr_stmt | print_stmt | del_stmt | pass_stmt | flow_stmt | import_stmt | global_stmt | exec_stmt | assert_stmt
 expr_stmt: testlist (augassign testlist | ('=' testlist)*)
! augassign: '+=' | '-=' | '*=' | '/=' | '%=' | '&=' | '|=' | '^=' | '<<=' | '>>=' | '**=' | '//='
 # For normal assignments, additional restrictions enforced by the interpreter
 print_stmt: 'print' ( [ test (',' test)* [','] ] | '>>' test [ (',' test)+ [','] ] )
***************
*** 78,82 ****
 shift_expr: arith_expr (('<<'|'>>') arith_expr)*
 arith_expr: term (('+'|'-') term)*
! term: factor (('*'|'/'|'%') factor)*
 factor: ('+'|'-'|'~') factor | power
 power: atom trailer* ('**' factor)*
--- 78,82 ----
 shift_expr: arith_expr (('<<'|'>>') arith_expr)*
 arith_expr: term (('+'|'-') term)*
! term: factor (('*'|'/'|'%'|'//') factor)*
 factor: ('+'|'-'|'~') factor | power
 power: atom trailer* ('**' factor)*