B
     S]8                 @   sf   d Z ddlmZ ddlmZ ddlmZmZmZm	Z	m
Z
 ddlmZ ddlmZ G dd dejZd	S )
a  Fixer that changes map(F, ...) into list(map(F, ...)) unless there
exists a 'from future_builtins import map' statement in the top-level
namespace.

As a special case, map(None, X) is changed into list(X).  (This is
necessary because the semantics are changed in this case -- the new
map(None, X) is equivalent to [(x,) for x in X].)

We avoid the transformation (except for the special case mentioned
above) if the map() call is directly contained in iter(<>), list(<>),
tuple(<>), sorted(<>), ...join(<>), or for V in <>:.

NOTE: This is still not correct if the original code was depending on
map(F, X, Y, ...) to go on until the longest argument is exhausted,
substituting None for missing values -- like zip(), it now stops as
soon as the shortest argument is exhausted.
   )token)
fixer_base)NameArgListCallListCompin_special_context)python_symbols)Nodec               @   s    e Zd ZdZdZdZdd ZdS )FixMapTaL  
    map_none=power<
        'map'
        trailer< '(' arglist< 'None' ',' arg=any [','] > ')' >
        [extra_trailers=trailer*]
    >
    |
    map_lambda=power<
        'map'
        trailer<
            '('
            arglist<
                lambdef< 'lambda'
                         (fp=NAME | vfpdef< '(' fp=NAME ')'> ) ':' xp=any
                >
                ','
                it=any
            >
            ')'
        >
        [extra_trailers=trailer*]
    >
    |
    power<
        'map' args=trailer< '(' [any] ')' >
        [extra_trailers=trailer*]
    >
    zfuture_builtins.mapc             C   s  |  |rd S g }d|kr:x|d D ]}||  q$W |jjtjkrv| |d | }d|_t	t
d|g}n&d|krt|d  |d  |d  }ttj|g| dd	}nd
|kr|d  }d|_nd|krj|d }|jtjkrL|jd jtjkrL|jd jd jtjkrL|jd jd jdkrL| |d d S ttjt
d| g}d|_t|rxd S ttjt
dt|gg| }d|_|j|_|S )NZextra_trailerszYou should use a for loop here listZ
map_lambdaZxpfpit)prefixZmap_noneargargs       Nonezjcannot convert map(None, ...) with multiple arguments because map() now truncates to the shortest sequencemap)Zshould_skipappendZcloneparenttypesymsZsimple_stmtZwarningr   r   r   r   r
   ZpowerZtrailerZchildrenZarglistr   NAMEvaluer   r   )selfZnodeZresultsZtrailerstnewr    r    &lib/python3.7/lib2to3/fixes/fix_map.py	transform@   sF    



zFixMap.transformN)__name__
__module____qualname__ZBM_compatibleZPATTERNZskip_onr"   r    r    r    r!   r      s   r   N)__doc__Zpgen2r   r   r   Z
fixer_utilr   r   r   r   r   Zpygramr	   r   Zpytreer
   ZConditionalFixr   r    r    r    r!   <module>   s   